diff --git a/build.gradle b/build.gradle
index a5f7a101c..f4f48eac9 100644
--- a/build.gradle
+++ b/build.gradle
@@ -89,7 +89,7 @@ subprojects {
         ivy {
             url 'https://ci.athion.net/job'
             layout 'pattern', {
-                artifact '/[organisation]/[revision]/artifact/[module].[ext]'
+                artifact '/[organisation]/[module]/artifact/[revision].[ext]'
             }
         }
     }
diff --git a/worldedit-bukkit/build.gradle b/worldedit-bukkit/build.gradle
index fa20b2491..a8b71befb 100644
--- a/worldedit-bukkit/build.gradle
+++ b/worldedit-bukkit/build.gradle
@@ -13,6 +13,9 @@ configurations.all { Configuration it ->
     it.resolutionStrategy { ResolutionStrategy rs ->
         rs.force("com.google.guava:guava:21.0")
     }
+    it.resolutionStrategy { ResolutionStrategy rs ->
+        rs.force("it.unimi.dsi:fastutil:8.2.1")
+    }
 }
 
 dependencies {
@@ -21,6 +24,7 @@ dependencies {
     api project(':worldedit-libs:core') // TODO remove once core can compile
     api project(':worldedit-libs:bukkit')
     compileOnly 'com.sk89q:dummypermscompat:1.10'
+    compile "it.unimi.dsi:fastutil:8.2.1"
     testCompile 'org.mockito:mockito-core:1.9.0-rc1'
     implementation('org.apache.logging.log4j:log4j-slf4j-impl:2.8.1'){transitive = false}
     compile 'com.destroystokyo.paper:paper-api:1.14.4-R0.1-SNAPSHOT'
@@ -42,6 +46,12 @@ dependencies {
     implementation('com.wasteofplastic:askyblock:3.0.8.2'){transitive = false}
 }
 
+shadowJar {
+    relocate("it.unimi.dsi.fastutil", "com.sk89q.worldedit.bukkit.fastutil") {
+        include("it.unimi.dsi:fastutil")
+    }
+}
+
 processResources {
     from('src/main/resources') {
         expand(
diff --git a/worldedit-core/build.gradle b/worldedit-core/build.gradle
index 815f39a09..53e79bbda 100644
--- a/worldedit-core/build.gradle
+++ b/worldedit-core/build.gradle
@@ -15,6 +15,9 @@ configurations.all { Configuration it ->
     it.resolutionStrategy { ResolutionStrategy rs ->
         rs.force("com.google.guava:guava:21.0")
     }
+    it.resolutionStrategy { ResolutionStrategy rs ->
+        rs.force("it.unimi.dsi:fastutil:8.2.1")
+    }
 }
 
 dependencies {
@@ -28,6 +31,7 @@ dependencies {
     compile 'com.google.code.gson:gson:2.8.0'
     compile 'com.googlecode.json-simple:json-simple:1.1.1'
     compile 'org.slf4j:slf4j-api:1.7.26'
+    compile "it.unimi.dsi:fastutil:8.2.1"
 
     compileOnly project(':worldedit-libs:core:ap')
     annotationProcessor project(':worldedit-libs:core:ap')
@@ -46,6 +50,11 @@ dependencies {
     compile 'com.mojang:datafixerupper:1.0.20'
     compile 'com.github.luben:zstd-jni:1.1.1'
     compile 'co.aikar:fastutil-lite:1.0'
+    testImplementation ("org.junit.jupiter:junit-jupiter-api:5.5.0")
+    testImplementation ("org.junit.jupiter:junit-jupiter-params:5.5.0")
+    testImplementation ("org.mockito:mockito-core:3.0.0")
+    testImplementation ("org.mockito:mockito-junit-jupiter:3.0.0")
+    testRuntime ("org.junit.jupiter:junit-jupiter-engine:5.5.0")
 }
 
 tasks.withType(JavaCompile).configureEach {
diff --git a/worldedit-core/src/main/java/com/boydti/fawe/util/RandomTextureUtil.java b/worldedit-core/src/main/java/com/boydti/fawe/util/RandomTextureUtil.java
index 715eb141e..fbcc60bab 100644
--- a/worldedit-core/src/main/java/com/boydti/fawe/util/RandomTextureUtil.java
+++ b/worldedit-core/src/main/java/com/boydti/fawe/util/RandomTextureUtil.java
@@ -1,6 +1,7 @@
 package com.boydti.fawe.util;
 
 import com.sk89q.worldedit.world.block.BlockType;
+import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
 import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
 
 import java.io.FileNotFoundException;
@@ -80,7 +81,7 @@ public class RandomTextureUtil extends CachedTextureUtil {
 
     @Override
     public BlockType getNearestBlock(int color) {
-        int offsetColor = offsets.getOrDefault(color, 0);
+        int offsetColor = offsets.getOrDefault((Object) color, 0);
         if (offsetColor != 0) {
             offsetColor = addRandomColor(color, offsetColor);
         } else {
diff --git a/worldedit-core/src/main/java/com/boydti/fawe/util/ReflectionUtils.java b/worldedit-core/src/main/java/com/boydti/fawe/util/ReflectionUtils.java
index 8c47fcf17..c7a4d706a 100644
--- a/worldedit-core/src/main/java/com/boydti/fawe/util/ReflectionUtils.java
+++ b/worldedit-core/src/main/java/com/boydti/fawe/util/ReflectionUtils.java
@@ -168,73 +168,73 @@ public class ReflectionUtils {
         }
     }
 
-    public static Object getHandle(final Object wrapper) {
+    public static Object getHandle(Object wrapper) {
         final Method getHandle = makeMethod(wrapper.getClass(), "getHandle");
         return callMethod(getHandle, wrapper);
     }
 
     //Utils
-    public static Method makeMethod(final Class<?> clazz, final String methodName, final Class<?>... parameters) {
+    public static Method makeMethod(Class<?> clazz, String methodName, Class<?>... parameters) {
         try {
             return clazz.getDeclaredMethod(methodName, parameters);
-        } catch (final NoSuchMethodException ex) {
+        } catch (NoSuchMethodException ex) {
             return null;
-        } catch (final Exception ex) {
+        } catch (Exception ex) {
             throw new RuntimeException(ex);
         }
     }
 
     @SuppressWarnings("unchecked")
-    public static <T> T callMethod(final Method method, final Object instance, final Object... parameters) {
+    public static <T> T callMethod(Method method, Object instance, Object... parameters) {
         if (method == null) {
             throw new RuntimeException("No such method");
         }
         method.setAccessible(true);
         try {
             return (T) method.invoke(instance, parameters);
-        } catch (final InvocationTargetException ex) {
+        } catch (InvocationTargetException ex) {
             throw new RuntimeException(ex.getCause());
-        } catch (final Exception ex) {
+        } catch (Exception ex) {
             throw new RuntimeException(ex);
         }
     }
 
     @SuppressWarnings("unchecked")
-    public static <T> Constructor<T> makeConstructor(final Class<?> clazz, final Class<?>... parameterTypes) {
+    public static <T> Constructor<T> makeConstructor(Class<?> clazz, Class<?>... parameterTypes) {
         try {
             return (Constructor<T>) clazz.getConstructor(parameterTypes);
-        } catch (final NoSuchMethodException ex) {
+        } catch (NoSuchMethodException ex) {
             return null;
-        } catch (final Exception ex) {
+        } catch (Exception ex) {
             throw new RuntimeException(ex);
         }
     }
 
-    public static <T> T callConstructor(final Constructor<T> constructor, final Object... paramaters) {
+    public static <T> T callConstructor(Constructor<T> constructor, Object... paramaters) {
         if (constructor == null) {
             throw new RuntimeException("No such constructor");
         }
         constructor.setAccessible(true);
         try {
             return constructor.newInstance(paramaters);
-        } catch (final InvocationTargetException ex) {
+        } catch (InvocationTargetException ex) {
             throw new RuntimeException(ex.getCause());
-        } catch (final Exception ex) {
+        } catch (Exception ex) {
             throw new RuntimeException(ex);
         }
     }
 
-    public static Field makeField(final Class<?> clazz, final String name) {
+    public static Field makeField(Class<?> clazz, String name) {
         try {
             return clazz.getDeclaredField(name);
-        } catch (final NoSuchFieldException ex) {
+        } catch (NoSuchFieldException ex) {
             return null;
-        } catch (final Exception ex) {
+        } catch (Exception ex) {
             throw new RuntimeException(ex);
         }
     }
 
-    public static Field findField(final Class<?> clazz, final Class<?> type, int hasMods, int noMods) {
+    public static Field findField(Class<?> clazz, Class<?> type, int hasMods, int noMods) {
         for (Field field : clazz.getDeclaredFields()) {
             if (type == null || type.isAssignableFrom(field.getType())) {
                 int mods = field.getModifiers();
@@ -246,7 +246,7 @@ public class ReflectionUtils {
         return null;
     }
 
-    public static Field findField(final Class<?> clazz, final Class<?> type) {
+    public static Field findField(Class<?> clazz, Class<?> type) {
         for (Field field : clazz.getDeclaredFields()) {
             if (field.getType() == type) {
                 return setAccessible(field);
@@ -255,11 +255,11 @@ public class ReflectionUtils {
         return null;
     }
 
-    public static Method findMethod(final Class<?> clazz, final Class<?> returnType, Class... params) {
+    public static Method findMethod(Class<?> clazz, Class<?> returnType, Class... params) {
         return findMethod(clazz, 0, returnType, params);
     }
 
-    public static Method findMethod(final Class<?> clazz, int index, int hasMods, int noMods, final Class<?> returnType, Class... params) {
+    public static Method findMethod(Class<?> clazz, int index, int hasMods, int noMods, Class<?> returnType, Class... params) {
         outer:
         for (Method method : sortMethods(clazz.getDeclaredMethods())) {
             if (returnType == null || method.getReturnType() == returnType) {
@@ -296,49 +296,49 @@ public class ReflectionUtils {
         return fields;
     }
 
-    public static Method findMethod(final Class<?> clazz, int index, final Class<?> returnType, Class... params) {
+    public static Method findMethod(Class<?> clazz, int index, Class<?> returnType, Class... params) {
         return findMethod(clazz, index, 0, 0, returnType, params);
     }
 
-    public static <T extends AccessibleObject> T setAccessible(final T ao) {
+    public static <T extends AccessibleObject> T setAccessible(T ao) {
         ao.setAccessible(true);
         return ao;
     }
 
     @SuppressWarnings("unchecked")
-    public static <T> T getField(final Field field, final Object instance) {
+    public static <T> T getField(Field field, Object instance) {
         if (field == null) {
             throw new RuntimeException("No such field");
         }
         field.setAccessible(true);
         try {
             return (T) field.get(instance);
-        } catch (final Exception ex) {
+        } catch (Exception ex) {
             throw new RuntimeException(ex);
         }
     }
 
-    public static void setField(final Field field, final Object instance, final Object value) {
+    public static void setField(Field field, Object instance, Object value) {
         if (field == null) {
             throw new RuntimeException("No such field");
         }
         field.setAccessible(true);
         try {
             field.set(instance, value);
-        } catch (final Exception ex) {
+        } catch (Exception ex) {
             throw new RuntimeException(ex);
         }
     }
 
-    public static Class<?> getClass(final String name) {
+    public static Class<?> getClass(String name) {
         try {
             return Class.forName(name);
-        } catch (final ClassNotFoundException ex) {
+        } catch (ClassNotFoundException ex) {
             return null;
         }
     }
 
-    public static <T> Class<? extends T> getClass(final String name, final Class<T> superClass) {
+    public static <T> Class<? extends T> getClass(String name, Class<T> superClass) {
         try {
             return Class.forName(name).asSubclass(superClass);
         } catch (ClassCastException | ClassNotFoundException ex) {
@@ -353,7 +353,7 @@ public class ReflectionUtils {
      * @param clazz class
      * @return RefClass based on passed class
      */
-    public static RefClass getRefClass(final Class clazz) {
+    public static RefClass getRefClass(Class clazz) {
         return new RefClass(clazz);
     }
 
@@ -363,7 +363,7 @@ public class ReflectionUtils {
     public static class RefClass {
         private final Class<?> clazz;
 
-        private RefClass(final Class<?> clazz) {
+        private RefClass(Class<?> clazz) {
             this.clazz = clazz;
         }
 
@@ -382,7 +382,7 @@ public class ReflectionUtils {
          * @param object the object to check
          * @return true if object is an instance of this class
          */
-        public boolean isInstance(final Object object) {
+        public boolean isInstance(Object object) {
             return this.clazz.isInstance(object);
         }
 
@@ -394,11 +394,11 @@ public class ReflectionUtils {
          * @return RefMethod object
          * @throws RuntimeException if method not found
          */
-        public RefMethod getMethod(final String name, final Object... types) throws NoSuchMethodException {
+        public RefMethod getMethod(String name, Object... types) throws NoSuchMethodException {
             try {
                 final Class[] classes = new Class[types.length];
                 int i = 0;
-                for (final Object e : types) {
+                for (Object e : types) {
                     if (e instanceof Class) {
                         classes[i++] = (Class) e;
                     } else if (e instanceof RefClass) {
@@ -409,10 +409,10 @@ public class ReflectionUtils {
                 }
                 try {
                     return new RefMethod(this.clazz.getMethod(name, classes));
-                } catch (final NoSuchMethodException ignored) {
+                } catch (NoSuchMethodException ignored) {
                     return new RefMethod(this.clazz.getDeclaredMethod(name, classes));
                 }
-            } catch (final Exception e) {
+            } catch (Exception e) {
                 throw new RuntimeException(e);
             }
         }
@@ -424,11 +424,11 @@ public class ReflectionUtils {
          * @return RefMethod object
          * @throws RuntimeException if constructor not found
          */
-        public RefConstructor getConstructor(final Object... types) {
+        public RefConstructor getConstructor(Object... types) {
             try {
                 final Class[] classes = new Class[types.length];
                 int i = 0;
-                for (final Object e : types) {
+                for (Object e : types) {
                     if (e instanceof Class) {
                         classes[i++] = (Class) e;
                     } else if (e instanceof RefClass) {
@@ -439,10 +439,10 @@ public class ReflectionUtils {
                 }
                 try {
                     return new RefConstructor(this.clazz.getConstructor(classes));
-                } catch (final NoSuchMethodException ignored) {
+                } catch (NoSuchMethodException ignored) {
                     return new RefConstructor(this.clazz.getDeclaredConstructor(classes));
                 }
-            } catch (final Exception e) {
+            } catch (Exception e) {
                 throw new RuntimeException(e);
             }
         }
@@ -454,10 +454,10 @@ public class ReflectionUtils {
          * @return RefMethod object
          * @throws RuntimeException if method not found
          */
-        public RefMethod findMethod(final Object... types) {
+        public RefMethod findMethod(Object... types) {
             final Class[] classes = new Class[types.length];
             int t = 0;
-            for (final Object e : types) {
+            for (Object e : types) {
                 if (e instanceof Class) {
                     classes[t++] = (Class) e;
                 } else if (e instanceof RefClass) {
@@ -470,12 +470,12 @@ public class ReflectionUtils {
             Collections.addAll(methods, this.clazz.getMethods());
             Collections.addAll(methods, this.clazz.getDeclaredMethods());
             findMethod:
-            for (final Method m : methods) {
+            for (Method m : methods) {
                 final Class<?>[] methodTypes = m.getParameterTypes();
                 if (methodTypes.length != classes.length) {
                     continue;
                 }
-                for (final Class aClass : classes) {
+                for (Class aClass : classes) {
                     if (!Arrays.equals(classes, methodTypes)) {
                         continue findMethod;
                     }
@@ -492,12 +492,12 @@ public class ReflectionUtils {
          * @return RefMethod object
          * @throws RuntimeException if method not found
          */
-        public RefMethod findMethodByName(final String... names) {
+        public RefMethod findMethodByName(String... names) {
             final List<Method> methods = new ArrayList<>();
             Collections.addAll(methods, this.clazz.getMethods());
             Collections.addAll(methods, this.clazz.getDeclaredMethods());
-            for (final Method m : methods) {
-                for (final String name : names) {
+            for (Method m : methods) {
+                for (String name : names) {
                     if (m.getName().equals(name)) {
                         return new RefMethod(m);
                     }
@@ -513,7 +513,7 @@ public class ReflectionUtils {
          * @return RefMethod
          * @throws RuntimeException if method not found
          */
-        public RefMethod findMethodByReturnType(final RefClass type) {
+        public RefMethod findMethodByReturnType(RefClass type) {
             return this.findMethodByReturnType(type.clazz);
         }
 
@@ -531,7 +531,7 @@ public class ReflectionUtils {
             final List<Method> methods = new ArrayList<>();
             Collections.addAll(methods, this.clazz.getMethods());
             Collections.addAll(methods, this.clazz.getDeclaredMethods());
-            for (final Method m : methods) {
+            for (Method m : methods) {
                 if (type.equals(m.getReturnType())) {
                     return new RefMethod(m);
                 }
@@ -546,11 +546,11 @@ public class ReflectionUtils {
          * @return RefConstructor
          * @throws RuntimeException if constructor not found
          */
-        public RefConstructor findConstructor(final int number) {
+        public RefConstructor findConstructor(int number) {
             final List<Constructor> constructors = new ArrayList<>();
             Collections.addAll(constructors, this.clazz.getConstructors());
             Collections.addAll(constructors, this.clazz.getDeclaredConstructors());
-            for (final Constructor m : constructors) {
+            for (Constructor m : constructors) {
                 if (m.getParameterTypes().length == number) {
                     return new RefConstructor(m);
                 }
@@ -565,14 +565,14 @@ public class ReflectionUtils {
          * @return RefField
          * @throws RuntimeException if field not found
          */
-        public RefField getField(final String name) {
+        public RefField getField(String name) {
             try {
                 try {
                     return new RefField(this.clazz.getField(name));
-                } catch (final NoSuchFieldException ignored) {
+                } catch (NoSuchFieldException ignored) {
                     return new RefField(this.clazz.getDeclaredField(name));
                 }
-            } catch (final Exception e) {
+            } catch (Exception e) {
                 throw new RuntimeException(e);
             }
         }
@@ -584,7 +584,7 @@ public class ReflectionUtils {
          * @return RefField
          * @throws RuntimeException if field not found
          */
-        public RefField findField(final RefClass type) {
+        public RefField findField(RefClass type) {
             return this.findField(type.clazz);
         }
 
@@ -602,7 +602,7 @@ public class ReflectionUtils {
             final List<Field> fields = new ArrayList<>();
             Collections.addAll(fields, this.clazz.getFields());
             Collections.addAll(fields, this.clazz.getDeclaredFields());
-            for (final Field f : fields) {
+            for (Field f : fields) {
                 if (type.equals(f.getType())) {
                     return new RefField(f);
                 }
@@ -617,7 +617,7 @@ public class ReflectionUtils {
     public static class RefMethod {
         private final Method method;
 
-        private RefMethod(final Method method) {
+        private RefMethod(Method method) {
             this.method = method;
             method.setAccessible(true);
         }
@@ -649,7 +649,7 @@ public class ReflectionUtils {
          * @param e object to which the method is applied
          * @return RefExecutor with method call(...)
          */
-        public RefExecutor of(final Object e) {
+        public RefExecutor of(Object e) {
             return new RefExecutor(e);
         }
 
@@ -659,10 +659,10 @@ public class ReflectionUtils {
          * @param params sent parameters
          * @return return value
          */
-        public Object call(final Object... params) {
+        public Object call(Object... params) {
             try {
                 return this.method.invoke(null, params);
-            } catch (final Exception e) {
+            } catch (Exception e) {
                 throw new RuntimeException(e);
             }
         }
@@ -670,7 +670,7 @@ public class ReflectionUtils {
         public class RefExecutor {
             final Object e;
 
-            public RefExecutor(final Object e) {
+            public RefExecutor(Object e) {
                 this.e = e;
             }
 
@@ -681,10 +681,10 @@ public class ReflectionUtils {
              * @return return value
              * @throws RuntimeException if something went wrong
              */
-            public Object call(final Object... params) {
+            public Object call(Object... params) {
                 try {
                     return RefMethod.this.method.invoke(this.e, params);
-                } catch (final Exception e) {
+                } catch (Exception e) {
                     throw new RuntimeException(e);
                 }
             }
@@ -697,7 +697,7 @@ public class ReflectionUtils {
     public static class RefConstructor {
         private final Constructor constructor;
 
-        private RefConstructor(final Constructor constructor) {
+        private RefConstructor(Constructor constructor) {
             this.constructor = constructor;
             constructor.setAccessible(true);
         }
@@ -723,10 +723,10 @@ public class ReflectionUtils {
          * @return new object
          * @throws RuntimeException if something went wrong
          */
-        public Object create(final Object... params) {
+        public Object create(Object... params) {
             try {
                 return this.constructor.newInstance(params);
-            } catch (final Exception e) {
+            } catch (Exception e) {
                 throw new RuntimeException(e);
             }
         }
@@ -735,7 +735,7 @@ public class ReflectionUtils {
     public static class RefField {
         private final Field field;
 
-        private RefField(final Field field) {
+        private RefField(Field field) {
             this.field = field;
             field.setAccessible(true);
         }
@@ -767,14 +767,14 @@ public class ReflectionUtils {
          * @param e applied object
          * @return RefExecutor with getter and setter
          */
-        public RefExecutor of(final Object e) {
+        public RefExecutor of(Object e) {
             return new RefExecutor(e);
         }
 
         public class RefExecutor {
             final Object e;
 
-            public RefExecutor(final Object e) {
+            public RefExecutor(Object e) {
                 this.e = e;
             }
 
@@ -783,10 +783,10 @@ public class ReflectionUtils {
              *
              * @param param value
              */
-            public void set(final Object param) {
+            public void set(Object param) {
                 try {
                     RefField.this.field.set(this.e, param);
-                } catch (final Exception e) {
+                } catch (Exception e) {
                     throw new RuntimeException(e);
                 }
             }
@@ -799,7 +799,7 @@ public class ReflectionUtils {
             public Object get() {
                 try {
                     return RefField.this.field.get(this.e);
-                } catch (final Exception e) {
+                } catch (Exception e) {
                     throw new RuntimeException(e);
                 }
             }
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/LocalConfiguration.java b/worldedit-core/src/main/java/com/sk89q/worldedit/LocalConfiguration.java
index 05e6ead54..e9db84e06 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/LocalConfiguration.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/LocalConfiguration.java
@@ -80,6 +80,7 @@ public abstract class LocalConfiguration {
     public int butcherMaxRadius = -1;
     public boolean allowSymlinks = false;
     public boolean serverSideCUI = true;
+    public boolean extendedYLimit = false;
 
     protected String[] getDefaultDisallowedBlocks() {
         List<BlockType> blockTypes = Lists.newArrayList(
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/command/BrushCommands.java b/worldedit-core/src/main/java/com/sk89q/worldedit/command/BrushCommands.java
index 72ec1431b..92a8a0e60 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/command/BrushCommands.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/command/BrushCommands.java
@@ -95,6 +95,7 @@ import com.sk89q.worldedit.function.mask.Mask;
 import com.sk89q.worldedit.function.mask.SingleBlockTypeMask;
 import com.sk89q.worldedit.function.operation.Operation;
 import com.sk89q.worldedit.function.pattern.Pattern;
+import com.sk89q.worldedit.internal.annotation.ClipboardMask;
 import com.sk89q.worldedit.internal.annotation.Range;
 import com.sk89q.worldedit.internal.expression.Expression;
 import com.sk89q.worldedit.internal.expression.runtime.EvaluationException;
@@ -153,9 +154,9 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.blendball")
     public BrushSettings blendBallBrush(Player player, LocalSession session,
         @Arg(desc = "The radius to sample for blending", def = "5")
-        Expression radiusOpt, InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
-        return set(session, context, new BlendBall()).setSize(radiusOpt);
+        Expression radius, InjectedValueAccess context) throws WorldEditException {
+        worldEdit.checkMaxBrushRadius(radius);
+        return set(session, context, new BlendBall()).setSize(radius);
     }
 
     @Command(
@@ -165,9 +166,9 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.erode")
     public BrushSettings erodeBrush(Player player, LocalSession session,
         @Arg(desc = "The radius for eroding", def = "5")
-            Expression radiusOpt, InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
-        return set(session, context, new ErodeBrush()).setSize(radiusOpt);
+            Expression radius, InjectedValueAccess context) throws WorldEditException {
+        worldEdit.checkMaxBrushRadius(radius);
+        return set(session, context, new ErodeBrush()).setSize(radius);
     }
 
     @Command(
@@ -177,9 +178,9 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.pull")
     public BrushSettings pullBrush(Player player, LocalSession session,
         @Arg(desc = "The radius to sample for blending", def = "5")
-        Expression radiusOpt, InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
-        return set(session, context, new RaiseBrush()).setSize(radiusOpt);
+        Expression radius, InjectedValueAccess context) throws WorldEditException {
+        worldEdit.checkMaxBrushRadius(radius);
+        return set(session, context, new RaiseBrush()).setSize(radius);
     }
 
     @Command(
@@ -189,9 +190,9 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.sphere")
     public BrushSettings circleBrush(Player player, EditSession editSession, LocalSession session, Pattern fill,
         @Arg(desc = "The radius to sample for blending", def = "5")
-        Expression radiusOpt, InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
-        return set(session, context, new CircleBrush(player)).setSize(radiusOpt).setFill(fill);
+        Expression radius, InjectedValueAccess context) throws WorldEditException {
+        worldEdit.checkMaxBrushRadius(radius);
+        return set(session, context, new CircleBrush(player)).setSize(radius).setFill(fill);
     }
 
     @Command(
@@ -204,14 +205,14 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.recursive")
     public BrushSettings recursiveBrush(Player player, LocalSession session, EditSession editSession, Pattern fill,
         @Arg(desc = "The radius to sample for blending", def = "5")
-            Expression radiusOpt,
+            Expression radius,
         @Switch(name = 'd', desc = "Apply in depth first order")
             boolean depthFirst,
         InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
+        worldEdit.checkMaxBrushRadius(radius);
         return set(session, context,
                 new RecurseBrush(depthFirst))
-                .setSize(radiusOpt)
+                .setSize(radius)
                 .setFill(fill)
                 .setMask(new IdMask(editSession));
     }
@@ -224,17 +225,17 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.line")
     public BrushSettings lineBrush(Player player, LocalSession session, Pattern fill,
         @Arg(desc = "The radius to sample for blending", def = "0")
-            Expression radiusOpt,
+            Expression radius,
         @Switch(name = 'h', desc = "Create only a shell")
             boolean shell,
         @Switch(name = 's', desc = "Selects the clicked point after drawing")
             boolean select,
         @Switch(name = 'f', desc = "Create a flat line")
             boolean flat, InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
+        worldEdit.checkMaxBrushRadius(radius);
         return set(session, context,
                 new LineBrush(shell, select, flat))
-                .setSize(radiusOpt)
+                .setSize(radius)
                 .setFill(fill);
     }
 
@@ -251,12 +252,12 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.spline")
     public BrushSettings splineBrush(Player player, EditSession editSession, LocalSession session, Pattern fill,
         @Arg(desc = "The radius to sample for blending", def = "25")
-        Expression radiusOpt, InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
-        player.print(BBC.BRUSH_SPLINE.format(radiusOpt));
+        Expression radius, InjectedValueAccess context) throws WorldEditException {
+        worldEdit.checkMaxBrushRadius(radius);
+        player.print(BBC.BRUSH_SPLINE.format(radius));
         return set(session, context,
                 new SplineBrush(player, session))
-                .setSize(radiusOpt)
+                .setSize(radius)
                 .setFill(fill);
     }
 
@@ -282,7 +283,7 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.spline")
     public BrushSettings catenaryBrush(LocalSession session, Pattern fill, @Arg(def = "1.2", desc = "Length of wire compared to distance between points") @Range(min = 1) double lengthFactor,
         @Arg(desc = "The radius to sample for blending", def = "0")
-            Expression radiusOpt,
+            Expression radius,
         @Switch(name = 'h', desc = "Create only a shell")
             boolean shell,
         @Switch(name = 's', desc = "Select the clicked point after drawing")
@@ -290,11 +291,11 @@ public class BrushCommands {
         @Switch(name = 'd', desc = "sags the catenary toward the facing direction")
             boolean facingDirection,
         InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
+        worldEdit.checkMaxBrushRadius(radius);
         Brush brush = new CatenaryBrush(shell, select, facingDirection, lengthFactor);
         return set(session, context,
                 new CatenaryBrush(shell, select, facingDirection, lengthFactor))
-                .setSize(radiusOpt)
+                .setSize(radius)
                 .setFill(fill);
     }
 
@@ -308,12 +309,12 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.surfacespline") // 0, 0, 0, 10, 0,
     public BrushSettings surfaceSpline(Player player, LocalSession session, Pattern fill,
         @Arg(desc = "The radius to sample for blending", def = "0")
-            Expression radiusOpt, @Arg(name = "tension", desc = "double", def = "0") double tension, @Arg(name = "bias", desc = "double", def = "0") double bias, @Arg(name = "continuity", desc = "double", def = "0") double continuity, @Arg(name = "quality", desc = "double", def = "10") double quality, InjectedValueAccess context) throws WorldEditException {
-        player.print(BBC.BRUSH_SPLINE.format(radiusOpt));
-        worldEdit.checkMaxBrushRadius(radiusOpt);
+            Expression radius, @Arg(name = "tension", desc = "double", def = "0") double tension, @Arg(name = "bias", desc = "double", def = "0") double bias, @Arg(name = "continuity", desc = "double", def = "0") double continuity, @Arg(name = "quality", desc = "double", def = "10") double quality, InjectedValueAccess context) throws WorldEditException {
+        player.print(BBC.BRUSH_SPLINE.format(radius));
+        worldEdit.checkMaxBrushRadius(radius);
         return set(session, context,
                 new SurfaceSpline(tension, bias, continuity, quality))
-                .setSize(radiusOpt)
+                .setSize(radius)
                 .setFill(fill);
     }
 
@@ -343,12 +344,12 @@ public class BrushCommands {
         @Arg(desc = "The pattern of blocks to set")
             Pattern pattern,
         @Arg(desc = "The radius of the sphere", def = "2")
-            Expression radiusOpt,
+            Expression radius,
         @Switch(name = 'h', desc = "Create hollow spheres instead")
             boolean hollow,
         @Switch(name = 'f', desc = "Create falling spheres instead")
             boolean falling, InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
+        worldEdit.checkMaxBrushRadius(radius);
         Brush brush;
         if (hollow) {
             brush = new HollowSphereBrush();
@@ -371,7 +372,7 @@ public class BrushCommands {
         }
         return set(session, context,
                 brush)
-                .setSize(radiusOpt)
+                .setSize(radius)
                 .setFill(pattern);
     }
 
@@ -385,12 +386,12 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.shatter")
     public BrushSettings shatterBrush(Player player, EditSession editSession, LocalSession session, Pattern fill,
         @Arg(desc = "The radius to sample for blending", def = "10")
-        Expression radiusOpt,
+        Expression radius,
         @Arg(desc = "Lines", def = "10") int count, InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
+        worldEdit.checkMaxBrushRadius(radius);
         return set(session, context,
                 new ShatterBrush(count))
-                .setSize(radiusOpt)
+                .setSize(radius)
                 .setFill(fill)
                 .setMask(new ExistingBlockMask(editSession));
     }
@@ -402,14 +403,14 @@ public class BrushCommands {
 )
     @CommandPermissions("worldedit.brush.stencil")
     public BrushSettings stencilBrush(Player player, LocalSession session, Pattern fill,
-                                      @Arg(name = "radius", desc = "Expression", def = "5") Expression radiusOpt,
+                                      @Arg(name = "radius", desc = "Expression", def = "5") Expression radius,
                                       @Arg(name = "image", desc = "String", def = "") String image,
                                       @Arg(def = "0", desc = "rotation") @Range(min = 0, max = 360) int rotation,
                                       @Arg(name = "yscale", desc = "double", def = "1") double yscale,
                                       @Switch(name = 'w', desc = "Apply at maximum saturation") boolean onlyWhite,
                                       @Switch(name = 'r', desc = "Apply random rotation") boolean randomRotate,
                                       InjectedValueAccess context) throws WorldEditException, FileNotFoundException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
+        worldEdit.checkMaxBrushRadius(radius);
         InputStream stream = getHeightmapStream(image);
         HeightBrush brush;
         try {
@@ -422,7 +423,7 @@ public class BrushCommands {
         }
         return set(session, context,
                 brush)
-                .setSize(radiusOpt)
+                .setSize(radius)
                 .setFill(fill);
     }
 
@@ -432,14 +433,14 @@ public class BrushCommands {
             desc = "Use a height map to paint a surface",
             descFooter = "Use a height map to paint any surface.\n")
     @CommandPermissions("worldedit.brush.stencil")
-    public BrushSettings imageBrush(LocalSession session, @Arg(name = "radius", desc = "Expression", def = "5") Expression radiusOpt,
+    public BrushSettings imageBrush(LocalSession session, @Arg(name = "radius", desc = "Expression", def = "5") Expression radius,
             ProvideBindings.ImageUri imageUri,
             @Arg(def = "1", desc = "scale height") @Range(min = Double.MIN_NORMAL) double yscale,
             @Switch(name = 'a', desc = "Use image Alpha") boolean alpha,
             @Switch(name = 'f', desc = "Blend the image with existing terrain") boolean fadeOut,
             InjectedValueAccess context) throws WorldEditException, IOException {
         BufferedImage image = imageUri.load();
-        worldEdit.checkMaxBrushRadius(radiusOpt);
+        worldEdit.checkMaxBrushRadius(radius);
         if (yscale != 1) {
             ImageUtil.scaleAlpha(image, yscale);
             alpha = true;
@@ -451,7 +452,7 @@ public class BrushCommands {
         ImageBrush brush = new ImageBrush(image, session, alpha);
         return set(session, context,
                 brush)
-                .setSize(radiusOpt);
+                .setSize(radius);
     }
 
     @Command(
@@ -465,10 +466,10 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.surface")
     public BrushSettings surfaceBrush(LocalSession session, Pattern fill,
         @Arg(name = "radius", desc = "Expression", def = "5")
-            Expression radiusOpt,
+            Expression radius,
         InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
-        return set(session, context, new SurfaceSphereBrush()).setFill(fill).setSize(radiusOpt);
+        worldEdit.checkMaxBrushRadius(radius);
+        return set(session, context, new SurfaceSphereBrush()).setFill(fill).setSize(radius);
     }
 
     @Command(
@@ -478,8 +479,8 @@ public class BrushCommands {
                    "Video: https://youtu.be/RPZIaTbqoZw?t=34s"
     )
     @CommandPermissions("worldedit.brush.scatter")
-    public BrushSettings scatterBrush(LocalSession session, Pattern fill, @Arg(name = "radius", desc = "Expression", def = "5") Expression radiusOpt, @Arg(name = "points", desc = "double", def = "5") double pointsOpt, @Arg(name = "distance", desc = "double", def = "1") double distanceOpt, @Switch(name = 'o', desc = "Overlay the block") boolean overlay, InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
+    public BrushSettings scatterBrush(LocalSession session, Pattern fill, @Arg(name = "radius", desc = "Expression", def = "5") Expression radius, @Arg(name = "points", desc = "double", def = "5") double pointsOpt, @Arg(name = "distance", desc = "double", def = "1") double distanceOpt, @Switch(name = 'o', desc = "Overlay the block") boolean overlay, InjectedValueAccess context) throws WorldEditException {
+        worldEdit.checkMaxBrushRadius(radius);
         Brush brush;
         if (overlay) {
             brush = new ScatterOverlayBrush((int) pointsOpt, (int) distanceOpt);
@@ -488,7 +489,7 @@ public class BrushCommands {
         }
         return set(session, context,
                 brush)
-                .setSize(radiusOpt)
+                .setSize(radius)
                 .setFill(fill);
     }
 
@@ -498,8 +499,8 @@ public class BrushCommands {
             desc = "Scatter a schematic on a surface"
     )
     @CommandPermissions("worldedit.brush.populateschematic")
-    public BrushSettings scatterSchemBrush(Player player, LocalSession session, Mask mask, @Arg(name = "clipboard", desc = "Clipboard uri") String clipboardStr, @Arg(name = "radius", desc = "Expression", def = "30") Expression radiusOpt, @Arg(name = "density", desc = "double", def = "50") double density, @Switch(name = 'r', desc = "Apply random rotation") boolean rotate, InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
+    public BrushSettings scatterSchemBrush(Player player, LocalSession session, Mask mask, @Arg(name = "clipboard", desc = "Clipboard uri") String clipboardStr, @Arg(name = "radius", desc = "Expression", def = "30") Expression radius, @Arg(name = "density", desc = "double", def = "50") double density, @Switch(name = 'r', desc = "Apply random rotation") boolean rotate, InjectedValueAccess context) throws WorldEditException {
+        worldEdit.checkMaxBrushRadius(radius);
         try {
             MultiClipboardHolder clipboards = ClipboardFormats.loadAllFromInput(player, clipboardStr, null, true);
             if (clipboards == null) {
@@ -513,7 +514,7 @@ public class BrushCommands {
             }
 
             return set(session, context,
-                    new PopulateSchem(mask, holders, (int) density, rotate)).setSize(radiusOpt);
+                    new PopulateSchem(mask, holders, (int) density, rotate)).setSize(radius);
         } catch (IOException e) {
             throw new RuntimeException(e);
         }
@@ -541,9 +542,9 @@ public class BrushCommands {
                    "Note: The seeds define how many splotches there are, recursion defines how large, solid defines whether the pattern is applied per seed, else per block."
     )
     @CommandPermissions("worldedit.brush.splatter")
-    public BrushSettings splatterBrush(LocalSession session, Pattern fill, @Arg(name = "radius", desc = "Expression", def = "5") Expression radiusOpt, @Arg(name = "points", desc = "double", def = "1") double pointsOpt, @Arg(name = "recursion", desc = "double", def = "5") double recursion, @Arg(name = "solid", desc = "boolean", def = "true") boolean solid, InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
-        return set(session, context, new SplatterBrush((int) pointsOpt, (int) recursion, solid)).setSize(radiusOpt).setFill(fill);
+    public BrushSettings splatterBrush(LocalSession session, Pattern fill, @Arg(name = "radius", desc = "Expression", def = "5") Expression radius, @Arg(name = "points", desc = "double", def = "1") double pointsOpt, @Arg(name = "recursion", desc = "double", def = "5") double recursion, @Arg(name = "solid", desc = "boolean", def = "true") boolean solid, InjectedValueAccess context) throws WorldEditException {
+        worldEdit.checkMaxBrushRadius(radius);
+        return set(session, context, new SplatterBrush((int) pointsOpt, (int) recursion, solid)).setSize(radius).setFill(fill);
     }
 
     @Command(
@@ -574,13 +575,13 @@ public class BrushCommands {
         @Arg(desc = "The pattern of blocks to set")
             Pattern pattern,
         @Arg(desc = "The radius of the cylinder", def = "2")
-            Expression radiusOpt,
+            Expression radius,
         @Arg(desc = "The height of the cylinder", def = "1")
             int height,
         @Switch(name = 'h', desc = "Create hollow cylinders instead")
             boolean hollow,
         InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
+        worldEdit.checkMaxBrushRadius(radius);
         worldEdit.checkMaxBrushRadius(height);
 
         BrushSettings settings;
@@ -589,7 +590,7 @@ public class BrushCommands {
         } else {
             settings = set(session, context, new CylinderBrush(height));
         }
-        settings.setSize(radiusOpt)
+        settings.setSize(radius)
                 .setFill(pattern);
         return settings;
     }
@@ -604,7 +605,7 @@ public class BrushCommands {
                    "stood relative to the copied area when you copied it."
     )
     @CommandPermissions("worldedit.brush.clipboard")
-    public BrushSettings clipboardBrush(LocalSession session,
+    public BrushSettings clipboardBrush(Player player,LocalSession session,
                                @Switch(name = 'a', desc = "Don't paste air from the clipboard")
                                    boolean ignoreAir,
                                @Switch(name = 'o', desc = "Paste starting at the target location, instead of centering on it")
@@ -614,17 +615,21 @@ public class BrushCommands {
                                @Switch(name = 'b', desc = "Paste biomes if available")
                                    boolean pasteBiomes,
                                @ArgFlag(name = 'm', desc = "Skip blocks matching this mask in the clipboard", def = "")
+                               @ClipboardMask
                                    Mask sourceMask,
         InjectedValueAccess context) throws WorldEditException {
         ClipboardHolder holder = session.getClipboard();
         Clipboard clipboard = holder.getClipboard();
+        ClipboardHolder newHolder = new ClipboardHolder(clipboard);
+        newHolder.setTransform(holder.getTransform());
 
         BlockVector3 size = clipboard.getDimensions();
 
-        worldEdit.checkMaxBrushRadius(size.getBlockX());
-        worldEdit.checkMaxBrushRadius(size.getBlockY());
-        worldEdit.checkMaxBrushRadius(size.getBlockZ());
-        return set(session, context, new ClipboardBrush(holder, ignoreAir, usingOrigin, !skipEntities, pasteBiomes, sourceMask));
+        worldEdit.checkMaxBrushRadius(size.getBlockX() / 2D - 1);
+        worldEdit.checkMaxBrushRadius(size.getBlockY() / 2D - 1);
+        worldEdit.checkMaxBrushRadius(size.getBlockZ() / 2D - 1);
+
+        return set(session, context, new ClipboardBrush(newHolder, ignoreAir, usingOrigin, !skipEntities, pasteBiomes, sourceMask));
     }
 
     @Command(
@@ -635,12 +640,12 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.smooth")
     public BrushSettings smoothBrush(Player player, LocalSession session, EditSession editSession,
                             @Arg(desc = "The radius to sample for softening", def = "2")
-                                Expression radiusOpt,
+                                Expression radius,
                             @Arg(desc = "The number of iterations to perform", def = "4")
                                 int iterations,
                             @Arg(desc = "The mask of blocks to use for the heightmap", def = "")
                                 Mask maskOpt, InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
+        worldEdit.checkMaxBrushRadius(radius);
 
         FawePlayer fp = FawePlayer.wrap(player);
         FaweLimit limit = Settings.IMP.getLimit(fp);
@@ -648,7 +653,7 @@ public class BrushCommands {
 
         return set(session, context,
                 new SmoothBrush(iterations, maskOpt))
-                .setSize(radiusOpt);
+                .setSize(radius);
     }
 
     @Command(
@@ -659,14 +664,14 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.ex")
     public BrushSettings extinguishBrush(Player player, LocalSession session, EditSession editSession,
                                 @Arg(desc = "The radius to extinguish", def = "5")
-                                    Expression radiusOpt,
+                                    Expression radius,
         InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
+        worldEdit.checkMaxBrushRadius(radius);
 
         Pattern fill = BlockTypes.AIR.getDefaultState();
         return set(session, context,
                 new SphereBrush())
-                .setSize(radiusOpt)
+                .setSize(radius)
                 .setFill(fill)
                 .setMask(new SingleBlockTypeMask(editSession, BlockTypes.FIRE));
     }
@@ -679,15 +684,15 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.gravity")
     public BrushSettings gravityBrush(Player player, LocalSession session,
         @Arg(desc = "The radius to apply gravity in", def = "5")
-        Expression radiusOpt,
+        Expression radius,
         @Switch(name = 'h', desc = "Affect blocks starting at max Y, rather than the target location Y + radius")
             boolean fromMaxY,
         InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
+        worldEdit.checkMaxBrushRadius(radius);
 
         return set(session, context,
                 new GravityBrush(fromMaxY))
-                .setSize(radiusOpt);
+                .setSize(radius);
     }
 
     @Command(
@@ -702,8 +707,8 @@ public class BrushCommands {
                    "Snow Pic: https://i.imgur.com/Hrzn0I4.png"
     )
     @CommandPermissions("worldedit.brush.height")
-    public BrushSettings heightBrush(Player player, LocalSession session, @Arg(name = "radius", desc = "Expression", def = "5") Expression radiusOpt, @Arg(name = "image", desc = "String", def = "") String image, @Arg(def = "0", desc = "rotation") @Range(min = 0, max = 360) int rotation, @Arg(name = "yscale", desc = "double", def = "1") double yscale, @Switch(name = 'r', desc = "TODO") boolean randomRotate, @Switch(name = 'l', desc = "TODO") boolean layers, @Switch(name = 's', desc = "TODO") boolean dontSmooth, InjectedValueAccess context) throws WorldEditException, FileNotFoundException {
-        return terrainBrush(player, session, radiusOpt, image, rotation, yscale, false, randomRotate, layers, !dontSmooth, ScalableHeightMap.Shape.CONE, context);
+    public BrushSettings heightBrush(Player player, LocalSession session, @Arg(name = "radius", desc = "Expression", def = "5") Expression radius, @Arg(name = "image", desc = "String", def = "") String image, @Arg(def = "0", desc = "rotation") @Range(min = 0, max = 360) int rotation, @Arg(name = "yscale", desc = "double", def = "1") double yscale, @Switch(name = 'r', desc = "TODO") boolean randomRotate, @Switch(name = 'l', desc = "TODO") boolean layers, @Switch(name = 's', desc = "TODO") boolean dontSmooth, InjectedValueAccess context) throws WorldEditException, FileNotFoundException {
+        return terrainBrush(player, session, radius, image, rotation, yscale, false, randomRotate, layers, !dontSmooth, ScalableHeightMap.Shape.CONE, context);
     }
 
     @Command(
@@ -715,7 +720,7 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.height")
     public BrushSettings cliffBrush(Player player, LocalSession session,
         @Arg(name = "radius", desc = "Expression", def = "5")
-            Expression radiusOpt,
+            Expression radius,
         @Arg(name = "image", desc = "String", def = "")
             String image,
         @Arg(def = "0", desc = "rotation") @Step(90) @Range(min = 0, max = 360)
@@ -728,7 +733,7 @@ public class BrushCommands {
             boolean layers,
         @Switch(name = 's', desc = "Disables smoothing")
             boolean dontSmooth, InjectedValueAccess context) throws WorldEditException, FileNotFoundException {
-        return terrainBrush(player, session, radiusOpt, image, rotation, yscale, true, randomRotate, layers, !dontSmooth, ScalableHeightMap.Shape.CYLINDER, context);
+        return terrainBrush(player, session, radius, image, rotation, yscale, true, randomRotate, layers, !dontSmooth, ScalableHeightMap.Shape.CYLINDER, context);
     }
 
     @Command(
@@ -737,14 +742,14 @@ public class BrushCommands {
             desc = "This brush raises or lowers land towards the clicked point"
     )
     @CommandPermissions("worldedit.brush.height")
-    public BrushSettings flattenBrush(Player player, LocalSession session, @Arg(name = "radius", desc = "Expression", def = "5") Expression radiusOpt, @Arg(name = "image", desc = "String", def = "") String image, @Arg(def = "0", desc = "rotation") @Step(90) @Range(min = 0, max = 360) int rotation, @Arg(name = "yscale", desc = "double", def = "1") double yscale,
+    public BrushSettings flattenBrush(Player player, LocalSession session, @Arg(name = "radius", desc = "Expression", def = "5") Expression radius, @Arg(name = "image", desc = "String", def = "") String image, @Arg(def = "0", desc = "rotation") @Step(90) @Range(min = 0, max = 360) int rotation, @Arg(name = "yscale", desc = "double", def = "1") double yscale,
         @Switch(name = 'r', desc = "Enables random off-axis rotation")
             boolean randomRotate,
         @Switch(name = 'l', desc = "Will work on snow layers")
             boolean layers,
         @Switch(name = 's', desc = "Disables smoothing")
             boolean dontSmooth, InjectedValueAccess context) throws WorldEditException, FileNotFoundException {
-        return terrainBrush(player, session, radiusOpt, image, rotation, yscale, true, randomRotate, layers, !dontSmooth, ScalableHeightMap.Shape.CONE, context);
+        return terrainBrush(player, session, radius, image, rotation, yscale, true, randomRotate, layers, !dontSmooth, ScalableHeightMap.Shape.CONE, context);
     }
 
     private BrushSettings terrainBrush(Player player, LocalSession session, @Arg(name = "radius", desc = "Expression") Expression radius, String image, int rotation, double yscale, boolean flat, boolean randomRotate, boolean layers, boolean smooth, ScalableHeightMap.Shape shape, InjectedValueAccess context) throws WorldEditException, FileNotFoundException {
@@ -792,13 +797,13 @@ public class BrushCommands {
                    "Video: https://www.youtube.com/watch?v=RPZIaTbqoZw"
     )
     @CommandPermissions("worldedit.brush.copy")
-    public BrushSettings copy(Player player, LocalSession session, @Arg(name = "radius", desc = "Expression", def = "5") Expression radiusOpt, @Switch(name = 'r', desc = "Apply random rotation on paste") boolean randomRotate, @Switch(name = 'a', desc = "Apply auto view based rotation on paste") boolean autoRotate, InjectedValueAccess context) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
-        player.print(BBC.BRUSH_COPY.format(radiusOpt));
+    public BrushSettings copy(Player player, LocalSession session, @Arg(name = "radius", desc = "Expression", def = "5") Expression radius, @Switch(name = 'r', desc = "Apply random rotation on paste") boolean randomRotate, @Switch(name = 'a', desc = "Apply auto view based rotation on paste") boolean autoRotate, InjectedValueAccess context) throws WorldEditException {
+        worldEdit.checkMaxBrushRadius(radius);
+        player.print(BBC.BRUSH_COPY.format(radius));
 
         return set(session, context,
                 new CopyPastaBrush(player, session, randomRotate, autoRotate))
-                .setSize(radiusOpt);
+                .setSize(radius);
     }
 
     @Command(
@@ -826,7 +831,7 @@ public class BrushCommands {
     @CommandPermissions("worldedit.brush.butcher")
     public BrushSettings butcherBrush(Player player, LocalSession session, InjectedValueAccess context,
                                       @Arg(desc = "Radius to kill mobs in", def = "5")
-                                          Expression radiusOpt,
+                                          Expression radius,
                                       @Switch(name = 'p', desc = "Also kill pets")
                                           boolean killPets,
                                       @Switch(name = 'n', desc = "Also kill NPCs")
@@ -843,7 +848,7 @@ public class BrushCommands {
                                  boolean killFriendly,
                              @Switch(name = 'r', desc = "Also destroy armor stands")
                                  boolean killArmorStands) throws WorldEditException {
-        worldEdit.checkMaxBrushRadius(radiusOpt);
+        worldEdit.checkMaxBrushRadius(radius);
 
         CreatureButcher flags = new CreatureButcher(player);
         flags.or(CreatureButcher.Flags.FRIENDLY      , killFriendly); // No permission check here. Flags will instead be filtered by the subsequent calls.
@@ -857,7 +862,7 @@ public class BrushCommands {
 
         return set(session, context,
                 new ButcherBrush(flags))
-                .setSize(radiusOpt);
+                .setSize(radius);
     }
 
     public BrushSettings process(CommandLocals locals, BrushSettings settings) throws WorldEditException {
@@ -899,12 +904,12 @@ public class BrushCommands {
         @Arg(desc = "The shape of the region")
             RegionFactory shape,
         @Arg(desc = "The size of the brush", def = "5")
-            Expression radiusOpt,
+            Expression radius,
         @Arg(desc = "The density of the brush", def = "20")
             double density,
         @Arg(desc = "The type of tree to use")
             TreeGenerator.TreeType type) throws WorldEditException, EvaluationException {
-        setOperationBasedBrush(player, localSession, radiusOpt,
+        setOperationBasedBrush(player, localSession, radius,
             new Paint(new TreeGeneratorFactory(type), density / 100), shape, "worldedit.brush.forest");
     }
 
@@ -917,8 +922,8 @@ public class BrushCommands {
                       @Arg(desc = "The shape of the region")
                           RegionFactory shape,
                       @Arg(desc = "The size of the brush", def = "5")
-                          Expression radiusOpt) throws WorldEditException, EvaluationException {
-        setOperationBasedBrush(player, localSession, radiusOpt,
+                          Expression radius) throws WorldEditException, EvaluationException {
+        setOperationBasedBrush(player, localSession, radius,
             new Deform("y-=1"), shape, "worldedit.brush.raise");
     }
 
@@ -931,8 +936,8 @@ public class BrushCommands {
                       @Arg(desc = "The shape of the region")
                           RegionFactory shape,
                       @Arg(desc = "The size of the brush", def = "5")
-                                  Expression radiusOpt) throws WorldEditException, EvaluationException {
-        setOperationBasedBrush(player, localSession, radiusOpt,
+                                  Expression radius) throws WorldEditException, EvaluationException {
+        setOperationBasedBrush(player, localSession, radius,
             new Deform("y+=1"), shape, "worldedit.brush.lower");
     }
 
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/command/ClipboardCommands.java b/worldedit-core/src/main/java/com/sk89q/worldedit/command/ClipboardCommands.java
index 75075133c..41d6a5abf 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/command/ClipboardCommands.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/command/ClipboardCommands.java
@@ -62,6 +62,7 @@ import com.sk89q.worldedit.function.operation.ForwardExtentCopy;
 import com.sk89q.worldedit.function.operation.Operation;
 import com.sk89q.worldedit.function.operation.Operations;
 import com.sk89q.worldedit.function.pattern.Pattern;
+import com.sk89q.worldedit.internal.annotation.ClipboardMask;
 import com.sk89q.worldedit.internal.annotation.Direction;
 import com.sk89q.worldedit.internal.annotation.Selection;
 import com.sk89q.worldedit.math.BlockVector3;
@@ -441,6 +442,7 @@ public class ClipboardCommands {
                       @Switch(name = 'b', desc = "Paste biomes if available")
                           boolean pasteBiomes,
                       @ArgFlag(name = 'm', desc = "Only paste blocks matching this mask", def = "")
+                      @ClipboardMask
                           Mask sourceMask) throws WorldEditException {
 
         ClipboardHolder holder = session.getClipboard();
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/command/argument/FactoryConverter.java b/worldedit-core/src/main/java/com/sk89q/worldedit/command/argument/FactoryConverter.java
index d6259abf3..8b5a56f0c 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/command/argument/FactoryConverter.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/command/argument/FactoryConverter.java
@@ -19,6 +19,7 @@
 
 package com.sk89q.worldedit.command.argument;
 
+import com.sk89q.worldedit.EmptyClipboardException;
 import com.sk89q.worldedit.LocalSession;
 import com.sk89q.worldedit.WorldEdit;
 import com.sk89q.worldedit.blocks.BaseItem;
@@ -27,9 +28,14 @@ import com.sk89q.worldedit.extension.input.InputParseException;
 import com.sk89q.worldedit.extension.input.ParserContext;
 import com.sk89q.worldedit.extension.platform.Actor;
 import com.sk89q.worldedit.extent.Extent;
+import com.sk89q.worldedit.extent.transform.BlockTransformExtent;
 import com.sk89q.worldedit.function.mask.Mask;
 import com.sk89q.worldedit.function.pattern.Pattern;
+import com.sk89q.worldedit.internal.annotation.ClipboardMask;
 import com.sk89q.worldedit.internal.registry.AbstractFactory;
+import com.sk89q.worldedit.math.transform.Transform;
+import com.sk89q.worldedit.session.ClipboardHolder;
+import com.sk89q.worldedit.session.request.RequestExtent;
 import com.sk89q.worldedit.util.formatting.text.Component;
 import com.sk89q.worldedit.util.formatting.text.TextComponent;
 import com.sk89q.worldedit.world.World;
@@ -41,30 +47,53 @@ import org.enginehub.piston.converter.SuccessfulConversion;
 import org.enginehub.piston.inject.InjectedValueAccess;
 import org.enginehub.piston.inject.Key;
 
+import javax.annotation.Nullable;
 import java.util.List;
+import java.util.function.Consumer;
 import java.util.function.Function;
 
 public class FactoryConverter<T> implements ArgumentConverter<T> {
 
     public static void register(WorldEdit worldEdit, CommandManager commandManager) {
         commandManager.registerConverter(Key.of(Pattern.class),
-            new FactoryConverter<>(worldEdit, WorldEdit::getPatternFactory, "pattern"));
+            new FactoryConverter<>(worldEdit, WorldEdit::getPatternFactory, "pattern", null));
         commandManager.registerConverter(Key.of(Mask.class),
-            new FactoryConverter<>(worldEdit, WorldEdit::getMaskFactory, "mask"));
+            new FactoryConverter<>(worldEdit, WorldEdit::getMaskFactory, "mask", null));
         commandManager.registerConverter(Key.of(BaseItem.class),
-            new FactoryConverter<>(worldEdit, WorldEdit::getItemFactory, "item"));
+            new FactoryConverter<>(worldEdit, WorldEdit::getItemFactory, "item", null));
+
+        commandManager.registerConverter(Key.of(Mask.class, ClipboardMask.class),
+                new FactoryConverter<>(worldEdit, WorldEdit::getMaskFactory, "mask",
+                        context -> {
+                            try {
+                                ClipboardHolder holder = context.getSession().getClipboard();
+                                Transform transform = holder.getTransform();
+                                Extent target;
+                                if (transform.isIdentity()) {
+                                    target = holder.getClipboard();
+                                } else {
+                                    target = new BlockTransformExtent(holder.getClipboard(), transform);
+                                }
+                                context.setExtent(target);
+                            } catch (EmptyClipboardException e) {
+                                throw new IllegalStateException(e);
+                            }
+                        }));
     }
 
     private final WorldEdit worldEdit;
     private final Function<WorldEdit, AbstractFactory<T>> factoryExtractor;
     private final String description;
+    @Nullable private final Consumer<ParserContext> contextTweaker;
 
     private FactoryConverter(WorldEdit worldEdit,
                              Function<WorldEdit, AbstractFactory<T>> factoryExtractor,
-                             String description) {
+                             String description,
+                             @Nullable Consumer<ParserContext> contextTweaker) {
         this.worldEdit = worldEdit;
         this.factoryExtractor = factoryExtractor;
         this.description = description;
+        this.contextTweaker = contextTweaker;
     }
 
     @Override
@@ -80,10 +109,15 @@ public class FactoryConverter<T> implements ArgumentConverter<T> {
             if (extent instanceof World) {
                 parserContext.setWorld((World) extent);
             }
+            parserContext.setExtent(new RequestExtent());
         }
         parserContext.setSession(session);
         parserContext.setRestricted(true);
 
+        if (contextTweaker != null) {
+            contextTweaker.accept(parserContext);
+        }
+
         try {
             return SuccessfulConversion.fromSingle(
                 factoryExtractor.apply(worldEdit).parseFromInput(argument, parserContext)
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BiomeMaskParser.java b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BiomeMaskParser.java
index 9e38e2e82..21fc46c4f 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BiomeMaskParser.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BiomeMaskParser.java
@@ -78,6 +78,6 @@ public class BiomeMaskParser extends InputParser<Mask> {
             biomes.add(biome);
         }
 
-        return Masks.asMask(new BiomeMask2D(new RequestExtent(), biomes));
+        return Masks.asMask(new BiomeMask2D(context.getExtent(), biomes));
     }
 }
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BlockCategoryMaskParser.java b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BlockCategoryMaskParser.java
index ee7bebf44..5001d2c38 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BlockCategoryMaskParser.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BlockCategoryMaskParser.java
@@ -54,7 +54,7 @@ public class BlockCategoryMaskParser extends InputParser<Mask> {
         if (category == null) {
             throw new InputParseException("Unrecognised tag '" + input.substring(2) + '\'');
         } else {
-            return new BlockCategoryMask(new RequestExtent(), category);
+            return new BlockCategoryMask(context.getExtent(), category);
         }
     }
 }
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BlockStateMaskParser.java b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BlockStateMaskParser.java
index 95884b821..026aa712f 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BlockStateMaskParser.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BlockStateMaskParser.java
@@ -53,7 +53,7 @@ public class BlockStateMaskParser extends InputParser<Mask> {
         boolean strict = input.charAt(1) == '=';
         String states = input.substring(2 + (strict ? 1 : 0), input.length() - 1);
         try {
-            return new BlockStateMask(new RequestExtent(),
+            return new BlockStateMask(context.getExtent(),
                     Splitter.on(',').omitEmptyStrings().trimResults().withKeyValueSeparator('=').split(states),
                     strict);
         } catch (Exception e) {
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BlocksMaskParser.java b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BlocksMaskParser.java
index 8580eb8a1..1a8b6e0b7 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BlocksMaskParser.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/BlocksMaskParser.java
@@ -56,7 +56,7 @@ public class BlocksMaskParser extends InputParser<Mask> {
             if (holders.isEmpty()) {
                 return null;
             }
-            return new BlockMask(new RequestExtent(), holders);
+            return new BlockMask(context.getExtent(), holders);
         } catch (NoMatchException e) {
             return null;
         }
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/ExistingMaskParser.java b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/ExistingMaskParser.java
index 21feb6449..324bf0857 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/ExistingMaskParser.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/ExistingMaskParser.java
@@ -44,6 +44,6 @@ public class ExistingMaskParser extends SimpleInputParser<Mask> {
 
     @Override
     public Mask parseFromSimpleInput(String input, ParserContext context) {
-        return new ExistingBlockMask(new RequestExtent());
+        return new ExistingBlockMask(context.getExtent());
     }
 }
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/ExpressionMaskParser.java b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/ExpressionMaskParser.java
index a7d55e990..ed05f9b62 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/ExpressionMaskParser.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/ExpressionMaskParser.java
@@ -58,7 +58,7 @@ public class ExpressionMaskParser extends InputParser<Mask> {
         try {
             Expression exp = Expression.compile(input.substring(1), "x", "y", "z");
             WorldEditExpressionEnvironment env = new WorldEditExpressionEnvironment(
-                    new RequestExtent(), Vector3.ONE, Vector3.ZERO);
+                    context.getExtent(), Vector3.ONE, Vector3.ZERO);
             exp.setEnvironment(env);
             if (context.getActor() != null) {
                 SessionOwner owner = context.getActor();
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/OffsetMaskParser.java b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/OffsetMaskParser.java
index ede9b6c79..fa49aea32 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/OffsetMaskParser.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/OffsetMaskParser.java
@@ -62,7 +62,7 @@ public class OffsetMaskParser extends InputParser<Mask> {
         if (input.length() > 1) {
             submask = worldEdit.getMaskFactory().parseFromInput(input.substring(1), context);
         } else {
-            submask = new ExistingBlockMask(new RequestExtent());
+            submask = new ExistingBlockMask(context.getExtent());
         }
         OffsetMask offsetMask = new OffsetMask(submask, BlockVector3.at(0, firstChar == '>' ? -1 : 1, 0));
         return new MaskIntersection(offsetMask, Masks.negate(submask));
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/SolidMaskParser.java b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/SolidMaskParser.java
index f5ae3244a..4fafcfaea 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/SolidMaskParser.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/factory/parser/mask/SolidMaskParser.java
@@ -44,6 +44,6 @@ public class SolidMaskParser extends SimpleInputParser<Mask> {
 
     @Override
     public Mask parseFromSimpleInput(String input, ParserContext context) {
-        return new SolidBlockMask(new RequestExtent());
+        return new SolidBlockMask(context.getExtent());
     }
 }
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/extent/reorder/ChunkBatchingExtent.java b/worldedit-core/src/main/java/com/sk89q/worldedit/extent/reorder/ChunkBatchingExtent.java
index 112708924..bf98dc45a 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/extent/reorder/ChunkBatchingExtent.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/extent/reorder/ChunkBatchingExtent.java
@@ -19,8 +19,7 @@
 
 package com.sk89q.worldedit.extent.reorder;
 
-import com.google.common.collect.Table;
-import com.google.common.collect.TreeBasedTable;
+import com.google.common.collect.ImmutableSortedSet;
 import com.sk89q.worldedit.WorldEditException;
 import com.sk89q.worldedit.extent.AbstractBufferingExtent;
 import com.sk89q.worldedit.extent.Extent;
@@ -28,15 +27,14 @@ import com.sk89q.worldedit.function.operation.Operation;
 import com.sk89q.worldedit.function.operation.RunContext;
 import com.sk89q.worldedit.math.BlockVector2;
 import com.sk89q.worldedit.math.BlockVector3;
+import com.sk89q.worldedit.math.RegionOptimizedComparator;
+import com.sk89q.worldedit.util.collection.BlockMap;
 import com.sk89q.worldedit.world.block.BaseBlock;
 import com.sk89q.worldedit.world.block.BlockStateHolder;
-import java.util.Comparator;
-import java.util.HashSet;
+
 import java.util.Iterator;
 import java.util.List;
-import java.util.Map;
 import java.util.Optional;
-import java.util.Set;
 
 /**
  * A special extent that batches changes into Minecraft chunks. This helps
@@ -46,17 +44,7 @@ import java.util.Set;
  */
 public class ChunkBatchingExtent extends AbstractBufferingExtent {
 
-    /**
-     * Comparator optimized for sorting chunks by the region file they reside
-     * in. This allows for file caches to be used while loading the chunk.
-     */
-    private static final Comparator<BlockVector2> REGION_OPTIMIZED_SORT =
-            Comparator.comparing((BlockVector2 vec) -> vec.shr(5), BlockVector2.COMPARING_GRID_ARRANGEMENT)
-                    .thenComparing(BlockVector2.COMPARING_GRID_ARRANGEMENT);
-
-    private final Table<BlockVector2, BlockVector3, BaseBlock> batches =
-        TreeBasedTable.create(REGION_OPTIMIZED_SORT, BlockVector3.sortByCoordsYzx());
-    private final Set<BlockVector3> containedBlocks = new HashSet<>();
+    private final BlockMap blockMap = BlockMap.create();
     private boolean enabled;
 
     public ChunkBatchingExtent(Extent extent) {
@@ -80,32 +68,20 @@ public class ChunkBatchingExtent extends AbstractBufferingExtent {
         return enabled;
     }
 
-    private BlockVector2 getChunkPos(BlockVector3 location) {
-        return location.shr(4).toBlockVector2();
-    }
-
-    private BlockVector3 getInChunkPos(BlockVector3 location) {
-        return BlockVector3.at(location.getX() & 15, location.getY(), location.getZ() & 15);
-    }
     @Override
     public <B extends BlockStateHolder<B>> boolean setBlock(BlockVector3 location, B block) throws WorldEditException {
         if (!enabled) {
             return setDelegateBlock(location, block);
         }
-        BlockVector2 chunkPos = getChunkPos(location);
-        BlockVector3 inChunkPos = getInChunkPos(location);
-        batches.put(chunkPos, inChunkPos, block.toBaseBlock());
-        containedBlocks.add(location);
+        blockMap.put(location, block.toBaseBlock());
         return true;
     }
 
     @Override
     protected Optional<BaseBlock> getBufferedBlock(BlockVector3 position) {
-        if (!containedBlocks.contains(position)) {
-            return Optional.empty();
-        }
-        return Optional.of(batches.get(getChunkPos(position), getInChunkPos(position)));
+        return Optional.ofNullable(blockMap.get(position));
     }
+
     @Override
     protected Operation commitBefore() {
         if (!commitRequired()) {
@@ -114,24 +90,21 @@ public class ChunkBatchingExtent extends AbstractBufferingExtent {
         return new Operation() {
 
             // we get modified between create/resume -- only create this on resume to prevent CME
-            private Iterator<Map.Entry<BlockVector2, Map<BlockVector3, BaseBlock>>> batchIterator;
+            private Iterator<BlockVector3> iterator;
 
             @Override
             public Operation resume(RunContext run) throws WorldEditException {
-                if (batchIterator == null) {
-                    batchIterator = batches.rowMap().entrySet().iterator();
+                if (iterator == null) {
+                    iterator = ImmutableSortedSet.copyOf(RegionOptimizedComparator.INSTANCE,
+                        blockMap.keySet()).iterator();
                 }
-                if (!batchIterator.hasNext()) {
-                    return null;
+                while (iterator.hasNext()) {
+                    BlockVector3 position = iterator.next();
+                    BaseBlock block = blockMap.get(position);
+                    getExtent().setBlock(position, block);
                 }
-                Map.Entry<BlockVector2, Map<BlockVector3, BaseBlock>> next = batchIterator.next();
-                BlockVector3 chunkOffset = next.getKey().toBlockVector3().shl(4);
-                for (Map.Entry<BlockVector3, BaseBlock> block : next.getValue().entrySet()) {
-                    getExtent().setBlock(block.getKey().add(chunkOffset), block.getValue());
-                    containedBlocks.remove(block.getKey());
-                }
-                batchIterator.remove();
-                return this;
+                blockMap.clear();
+                return null;
             }
 
             @Override
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/extent/reorder/MultiStageReorder.java b/worldedit-core/src/main/java/com/sk89q/worldedit/extent/reorder/MultiStageReorder.java
index e650bf90a..733d6c7de 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/extent/reorder/MultiStageReorder.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/extent/reorder/MultiStageReorder.java
@@ -24,23 +24,23 @@ import com.sk89q.worldedit.extent.AbstractBufferingExtent;
 import com.sk89q.worldedit.extent.Extent;
 import com.sk89q.worldedit.function.operation.Operation;
 import com.sk89q.worldedit.function.operation.OperationQueue;
-import com.sk89q.worldedit.function.operation.SetLocatedBlocks;
+import com.sk89q.worldedit.function.operation.RunContext;
+import com.sk89q.worldedit.function.operation.SetBlockMap;
 import com.sk89q.worldedit.math.BlockVector3;
-import com.sk89q.worldedit.util.collection.LocatedBlockList;
+import com.sk89q.worldedit.util.collection.BlockMap;
 import com.sk89q.worldedit.world.block.BaseBlock;
 import com.sk89q.worldedit.world.block.BlockCategories;
 import com.sk89q.worldedit.world.block.BlockState;
 import com.sk89q.worldedit.world.block.BlockStateHolder;
 import com.sk89q.worldedit.world.block.BlockType;
 import com.sk89q.worldedit.world.block.BlockTypes;
+
 import java.util.ArrayList;
 import java.util.HashMap;
-import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Optional;
-import java.util.Set;
 
 /**
  * Re-orders blocks into several stages.
@@ -142,8 +142,7 @@ public class MultiStageReorder extends AbstractBufferingExtent implements Reorde
         priorityMap.put(BlockTypes.MOVING_PISTON, PlacementPriority.FINAL);
     }
 
-    private final Set<BlockVector3> containedBlocks = new HashSet<>();
-    private Map<PlacementPriority, LocatedBlockList> stages = new HashMap<>();
+    private Map<PlacementPriority, BlockMap> stages = new HashMap<>();
 
     private boolean enabled;
 
@@ -177,7 +176,7 @@ public class MultiStageReorder extends AbstractBufferingExtent implements Reorde
         this.enabled = enabled;
 
         for (PlacementPriority priority : PlacementPriority.values()) {
-            stages.put(priority, new LocatedBlockList());
+            stages.put(priority, BlockMap.create());
         }
     }
 
@@ -219,7 +218,7 @@ public class MultiStageReorder extends AbstractBufferingExtent implements Reorde
             return setDelegateBlock(location, block);
         }
 
-        BlockState existing = getBlock(location);
+        BlockState existing = getExtent().getBlock(location);
         PlacementPriority priority = getPlacementPriority(block);
         PlacementPriority srcPriority = getPlacementPriority(existing);
 
@@ -228,13 +227,13 @@ public class MultiStageReorder extends AbstractBufferingExtent implements Reorde
 
             switch (srcPriority) {
                 case FINAL:
-                    stages.get(PlacementPriority.CLEAR_FINAL).add(location, replacement);
+                    stages.get(PlacementPriority.CLEAR_FINAL).put(location, replacement);
                     break;
                 case LATE:
-                    stages.get(PlacementPriority.CLEAR_LATE).add(location, replacement);
+                    stages.get(PlacementPriority.CLEAR_LATE).put(location, replacement);
                     break;
                 case LAST:
-                    stages.get(PlacementPriority.CLEAR_LAST).add(location, replacement);
+                    stages.get(PlacementPriority.CLEAR_LAST).put(location, replacement);
                     break;
             }
 
@@ -243,16 +242,12 @@ public class MultiStageReorder extends AbstractBufferingExtent implements Reorde
             }
         }
 
-        stages.get(priority).add(location, block);
-        containedBlocks.add(location);
+        stages.get(priority).put(location, block.toBaseBlock());
         return !existing.equalsFuzzy(block);
     }
 
     @Override
     protected Optional<BaseBlock> getBufferedBlock(BlockVector3 position) {
-        if (!containedBlocks.contains(position)) {
-            return Optional.empty();
-        }
         return stages.values().stream()
             .map(blocks -> blocks.get(position))
             .filter(Objects::nonNull)
@@ -266,7 +261,17 @@ public class MultiStageReorder extends AbstractBufferingExtent implements Reorde
         }
         List<Operation> operations = new ArrayList<>();
         for (PlacementPriority priority : PlacementPriority.values()) {
-            operations.add(new SetLocatedBlocks(getExtent(), stages.get(priority)));
+            BlockMap blocks = stages.get(priority);
+            operations.add(new SetBlockMap(getExtent(), blocks) {
+                @Override
+                public Operation resume(RunContext run) throws WorldEditException {
+                    Operation operation = super.resume(run);
+                    if (operation == null) {
+                        blocks.clear();
+                    }
+                    return operation;
+                }
+            });
         }
 
         return new OperationQueue(operations);
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/function/operation/SetBlockMap.java b/worldedit-core/src/main/java/com/sk89q/worldedit/function/operation/SetBlockMap.java
new file mode 100644
index 000000000..863aadd03
--- /dev/null
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/function/operation/SetBlockMap.java
@@ -0,0 +1,60 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.function.operation;
+
+import com.sk89q.worldedit.WorldEditException;
+import com.sk89q.worldedit.extent.Extent;
+import com.sk89q.worldedit.math.BlockVector3;
+import com.sk89q.worldedit.util.LocatedBlock;
+import com.sk89q.worldedit.util.collection.BlockMap;
+import com.sk89q.worldedit.world.block.BaseBlock;
+
+import java.util.List;
+import java.util.Map;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+public class SetBlockMap implements Operation {
+
+    private final Extent extent;
+    private final BlockMap blocks;
+
+    public SetBlockMap(Extent extent, BlockMap blocks) {
+        this.extent = checkNotNull(extent);
+        this.blocks = checkNotNull(blocks);
+    }
+
+    @Override
+    public Operation resume(RunContext run) throws WorldEditException {
+        for (Map.Entry<BlockVector3, BaseBlock> entry : blocks.entrySet()) {
+            extent.setBlock(entry.getKey(), entry.getValue());
+        }
+        return null;
+    }
+
+    @Override
+    public void cancel() {
+    }
+
+    @Override
+    public void addStatusMessages(List<String> messages) {
+    }
+
+}
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/internal/annotation/ClipboardMask.java b/worldedit-core/src/main/java/com/sk89q/worldedit/internal/annotation/ClipboardMask.java
new file mode 100644
index 000000000..6b8be85e0
--- /dev/null
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/internal/annotation/ClipboardMask.java
@@ -0,0 +1,37 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.internal.annotation;
+
+import com.sk89q.worldedit.function.mask.Mask;
+import org.enginehub.piston.inject.InjectAnnotation;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Annotates a {@link Mask} parameter to use the clipboard as the extent instead of target World/EditSession.
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.PARAMETER)
+@InjectAnnotation
+public @interface ClipboardMask {
+}
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/internal/block/BlockStateIdAccess.java b/worldedit-core/src/main/java/com/sk89q/worldedit/internal/block/BlockStateIdAccess.java
new file mode 100644
index 000000000..c62b96225
--- /dev/null
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/internal/block/BlockStateIdAccess.java
@@ -0,0 +1,77 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.internal.block;
+
+import com.google.common.collect.BiMap;
+import com.google.common.collect.HashBiMap;
+import com.sk89q.worldedit.world.block.BlockState;
+import com.sk89q.worldedit.world.registry.BlockRegistry;
+
+import javax.annotation.Nullable;
+import java.util.BitSet;
+import java.util.OptionalInt;
+
+import static com.google.common.base.Preconditions.checkState;
+
+public final class BlockStateIdAccess {
+
+    private static final BiMap<BlockState, Integer> ASSIGNED_IDS = HashBiMap.create(2 << 13);
+
+    public static OptionalInt getBlockStateId(BlockState holder) {
+        Integer value = ASSIGNED_IDS.get(holder);
+        return value == null ? OptionalInt.empty() : OptionalInt.of(value);
+    }
+
+    public static @Nullable BlockState getBlockStateById(int id) {
+        return ASSIGNED_IDS.inverse().get(id);
+    }
+
+    /**
+     * For platforms that don't have an internal ID system,
+     * {@link BlockRegistry#getInternalBlockStateId(BlockState)} will return
+     * {@link OptionalInt#empty()}. In those cases, we will use our own ID system,
+     * since it's useful for other entries as well.
+     * @return an unused ID in WorldEdit's ID tracker
+     */
+    private static int provideUnusedWorldEditId() {
+        return usedIds.nextClearBit(0);
+    }
+
+    private static final BitSet usedIds = new BitSet();
+
+    public static void register(BlockState blockState, OptionalInt id) {
+        int i = id.orElseGet(BlockStateIdAccess::provideUnusedWorldEditId);
+        BlockState existing = ASSIGNED_IDS.inverse().get(i);
+        checkState(existing == null || existing == blockState,
+            "BlockState %s is using the same block ID (%s) as BlockState %s",
+            blockState, i, existing);
+        ASSIGNED_IDS.put(blockState, i);
+        usedIds.set(i);
+    }
+
+    public static void clear() {
+        ASSIGNED_IDS.clear();
+        usedIds.clear();
+    }
+
+    private BlockStateIdAccess() {
+    }
+
+}
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/math/BitMath.java b/worldedit-core/src/main/java/com/sk89q/worldedit/math/BitMath.java
new file mode 100644
index 000000000..46fa66e73
--- /dev/null
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/math/BitMath.java
@@ -0,0 +1,52 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.math;
+
+public final class BitMath {
+
+    public static int mask(int bits) {
+        return ~(~0 << bits);
+    }
+
+    public static int unpackX(long packed) {
+        return extractSigned(packed, 0, 26);
+    }
+
+    public static int unpackZ(long packed) {
+        return extractSigned(packed, 26, 26);
+    }
+
+    public static int unpackY(long packed) {
+        return extractSigned(packed, 26 + 26, 12);
+    }
+
+    public static int extractSigned(long i, int shift, int bits) {
+        return fixSign((int) (i >> shift) & mask(bits), bits);
+    }
+
+    public static int fixSign(int i, int bits) {
+        // Using https://stackoverflow.com/a/29266331/436524
+        return i << (32 - bits) >> (32 - bits);
+    }
+
+    private BitMath() {
+    }
+
+}
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/math/BlockVector3.java b/worldedit-core/src/main/java/com/sk89q/worldedit/math/BlockVector3.java
index 77b5c7ba8..a940da291 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/math/BlockVector3.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/math/BlockVector3.java
@@ -20,6 +20,10 @@
 package com.sk89q.worldedit.math;
 
 import static com.google.common.base.Preconditions.checkArgument;
+import static com.sk89q.worldedit.math.BitMath.mask;
+import static com.sk89q.worldedit.math.BitMath.unpackX;
+import static com.sk89q.worldedit.math.BitMath.unpackY;
+import static com.sk89q.worldedit.math.BitMath.unpackZ;
 
 import com.sk89q.jnbt.CompoundTag;
 import com.sk89q.worldedit.extent.Extent;
@@ -67,6 +71,31 @@ public abstract class BlockVector3 {
         return new BlockVector3Imp(x, y, z);
     }
 
+    private static final int WORLD_XZ_MINMAX = 30_000_000;
+    private static final int WORLD_Y_MAX = 4095;
+
+    private static boolean isHorizontallyInBounds(int h) {
+        return -WORLD_XZ_MINMAX <= h && h <= WORLD_XZ_MINMAX;
+    }
+
+    public static boolean isLongPackable(BlockVector3 location) {
+        return isHorizontallyInBounds(location.getX()) &&
+            isHorizontallyInBounds(location.getZ()) &&
+            0 <= location.getY() && location.getY() <= WORLD_Y_MAX;
+    }
+
+    public static void checkLongPackable(BlockVector3 location) {
+        checkArgument(isLongPackable(location),
+            "Location exceeds long packing limits: %s", location);
+    }
+
+    private static final long BITS_26 = mask(26);
+    private static final long BITS_12 = mask(12);
+
+    public static BlockVector3 fromLongPackedForm(long packed) {
+        return at(unpackX(packed), unpackY(packed), unpackZ(packed));
+    }
+
     // thread-safe initialization idiom
     private static final class YzxOrderComparator {
 
@@ -154,6 +183,11 @@ public abstract class BlockVector3 {
 //        return orDefault.setComponents(getX(), getY() - 1, getZ());
 //    }
 
+    public long toLongPackedForm() {
+        checkLongPackable(this);
+        return (getX() & BITS_26) | ((getZ() & BITS_26) << 26) | (((getY() & (long) BITS_12) << (26 + 26)));
+    }
+
     /**
      * Get the X coordinate.
      *
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/math/RegionOptimizedChunkComparator.java b/worldedit-core/src/main/java/com/sk89q/worldedit/math/RegionOptimizedChunkComparator.java
new file mode 100644
index 000000000..d6d2d89d6
--- /dev/null
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/math/RegionOptimizedChunkComparator.java
@@ -0,0 +1,41 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.math;
+
+import java.util.Comparator;
+
+import static com.sk89q.worldedit.math.BlockVector2.COMPARING_GRID_ARRANGEMENT;
+
+/**
+ * Sort block positions by region, then chunk.
+ */
+public class RegionOptimizedChunkComparator {
+
+    private static final Comparator<BlockVector2> CHUNK_COMPARATOR =
+        Comparator.comparing((BlockVector2 chunkPos) -> chunkPos.shr(5), COMPARING_GRID_ARRANGEMENT)
+            .thenComparing(COMPARING_GRID_ARRANGEMENT);
+
+    public static final Comparator<BlockVector3> INSTANCE
+        = Comparator.comparing(blockPos -> blockPos.toBlockVector2().shr(4), CHUNK_COMPARATOR);
+
+    private RegionOptimizedChunkComparator() {
+    }
+
+}
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/math/RegionOptimizedComparator.java b/worldedit-core/src/main/java/com/sk89q/worldedit/math/RegionOptimizedComparator.java
new file mode 100644
index 000000000..ed715d703
--- /dev/null
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/math/RegionOptimizedComparator.java
@@ -0,0 +1,36 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.math;
+
+import java.util.Comparator;
+
+/**
+ * Sort block positions by region, chunk, and finally Y-Z-X.
+ */
+public class RegionOptimizedComparator {
+
+    public static final Comparator<BlockVector3> INSTANCE
+        = RegionOptimizedChunkComparator.INSTANCE
+        .thenComparing(BlockVector3.sortByCoordsYzx());
+
+    private RegionOptimizedComparator() {
+    }
+
+}
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/util/PropertiesConfiguration.java b/worldedit-core/src/main/java/com/sk89q/worldedit/util/PropertiesConfiguration.java
index 4a5a5cae6..0e98ee48c 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/util/PropertiesConfiguration.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/util/PropertiesConfiguration.java
@@ -121,6 +121,7 @@ public class PropertiesConfiguration extends LocalConfiguration {
         butcherMaxRadius = getInt("butcher-max-radius", butcherMaxRadius);
         allowSymlinks = getBool("allow-symbolic-links", allowSymlinks);
         serverSideCUI = getBool("server-side-cui", serverSideCUI);
+        extendedYLimit = getBool("extended-y-limit", extendedYLimit);
 
         LocalSession.MAX_HISTORY_SIZE = Math.max(15, getInt("history-size", 15));
 
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/util/YAMLConfiguration.java b/worldedit-core/src/main/java/com/sk89q/worldedit/util/YAMLConfiguration.java
index 2af093290..c65157fb1 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/util/YAMLConfiguration.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/util/YAMLConfiguration.java
@@ -125,6 +125,7 @@ public class YAMLConfiguration extends LocalConfiguration {
         String type = config.getString("shell-save-type", "").trim();
         shellSaveType = type.isEmpty() ? null : type;
 
+        extendedYLimit = config.getBoolean("compat.extended-y-limit", false);
     }
 
     public void unload() {
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/BlockMap.java b/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/BlockMap.java
new file mode 100644
index 000000000..2620a906e
--- /dev/null
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/BlockMap.java
@@ -0,0 +1,427 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.collection;
+
+import com.google.common.collect.AbstractIterator;
+import com.sk89q.worldedit.math.BlockVector3;
+import com.sk89q.worldedit.world.block.BaseBlock;
+import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
+import it.unimi.dsi.fastutil.ints.Int2ObjectMaps;
+import it.unimi.dsi.fastutil.longs.Long2ObjectMap;
+import it.unimi.dsi.fastutil.longs.Long2ObjectMaps;
+import it.unimi.dsi.fastutil.longs.Long2ObjectOpenHashMap;
+import it.unimi.dsi.fastutil.objects.ObjectIterator;
+
+import java.util.AbstractCollection;
+import java.util.AbstractMap;
+import java.util.AbstractSet;
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
+import java.util.function.BiConsumer;
+import java.util.function.BiFunction;
+import java.util.function.Function;
+
+import static com.sk89q.worldedit.math.BitMath.fixSign;
+import static com.sk89q.worldedit.math.BitMath.mask;
+
+/**
+ * A space-efficient map implementation for block locations.
+ */
+public class BlockMap extends AbstractMap<BlockVector3, BaseBlock> {
+
+    /* =========================
+       IF YOU MAKE CHANGES TO THIS CLASS
+       Re-run BlockMapTest with the blockmap.fulltesting=true system property.
+       Or just temporarily remove the annotation disabling the related tests.
+       ========================= */
+
+    public static BlockMap create() {
+        return new BlockMap();
+    }
+
+    public static BlockMap copyOf(Map<? extends BlockVector3, ? extends BaseBlock> source) {
+        return new BlockMap(source);
+    }
+
+    /*
+     * Stores blocks by sub-dividing them into smaller groups.
+     * A block location is 26 bits long for x + z, and usually
+     * 8 bits for y, although mods such as cubic chunks may
+     * expand this to infinite. We support up to 32 bits of y.
+     *
+     * Grouping key stores 20 bits x + z, 24 bits y.
+     * Inner key stores 6 bits x + z, 8 bits y.
+     * Order (lowest to highest) is x-z-y.
+     */
+
+    private static final long BITS_24 = mask(24);
+    private static final long BITS_20 = mask(20);
+    private static final int BITS_8 = mask(8);
+    private static final int BITS_6 = mask(6);
+
+    private static long toGroupKey(BlockVector3 location) {
+        return ((location.getX() >>> 6) & BITS_20)
+            | (((location.getZ() >>> 6) & BITS_20) << 20)
+            | (((location.getY() >>> 8) & BITS_24) << (20 + 20));
+    }
+
+    private static int toInnerKey(BlockVector3 location) {
+        return (location.getX() & BITS_6)
+            | ((location.getZ() & BITS_6) << 6)
+            | ((location.getY() & BITS_8) << (6 + 6));
+    }
+
+    private static final long GROUP_X = BITS_20;
+    private static final long GROUP_Z = BITS_20 << 20;
+    private static final long GROUP_Y = BITS_24 << (20 + 20);
+    private static final int INNER_X = BITS_6;
+    private static final int INNER_Z = BITS_6 << 6;
+    private static final int INNER_Y = BITS_8 << (6 + 6);
+
+    private static BlockVector3 reconstructLocation(long group, int inner) {
+        int groupX = (int) ((group & GROUP_X) << 6);
+        int x = fixSign(groupX | (inner & INNER_X), 26);
+        int groupZ = (int) ((group & GROUP_Z) >>> (20 - 6));
+        int z = fixSign(groupZ | ((inner & INNER_Z) >>> 6), 26);
+        int groupY = (int) ((group & GROUP_Y) >>> (20 + 20 - 8));
+        int y = groupY | ((inner & INNER_Y) >>> (6 + 6));
+        return BlockVector3.at(x, y, z);
+    }
+
+    private final Long2ObjectMap<SubBlockMap> maps = new Long2ObjectOpenHashMap<>(4, 1f);
+    private Set<Entry<BlockVector3, BaseBlock>> entrySet;
+    private Collection<BaseBlock> values;
+
+    private BlockMap() {
+    }
+
+    private BlockMap(Map<? extends BlockVector3, ? extends BaseBlock> source) {
+        putAll(source);
+    }
+
+    private SubBlockMap getOrCreateMap(long groupKey) {
+        return maps.computeIfAbsent(groupKey, k -> new SubBlockMap());
+    }
+
+    private SubBlockMap getOrEmptyMap(long groupKey) {
+        return maps.getOrDefault(groupKey, SubBlockMap.EMPTY);
+    }
+
+    /**
+     * Apply the function the the map at {@code groupKey}, and if the function empties the map,
+     * delete it from {@code maps}.
+     */
+    private <R> R cleanlyModifyMap(long groupKey, Function<Int2ObjectMap<BaseBlock>, R> func) {
+        SubBlockMap map = maps.get(groupKey);
+        if (map != null) {
+            R result = func.apply(map);
+            if (map.isEmpty()) {
+                maps.remove(groupKey);
+            }
+            return result;
+        }
+        map = new SubBlockMap();
+        R result = func.apply(map);
+        if (!map.isEmpty()) {
+            maps.put(groupKey, map);
+        }
+        return result;
+    }
+
+    @Override
+    public BaseBlock put(BlockVector3 key, BaseBlock value) {
+        return getOrCreateMap(toGroupKey(key)).put(toInnerKey(key), value);
+    }
+
+    @Override
+    public BaseBlock getOrDefault(Object key, BaseBlock defaultValue) {
+        BlockVector3 vec = (BlockVector3) key;
+        return getOrEmptyMap(toGroupKey(vec))
+            .getOrDefault(toInnerKey(vec), defaultValue);
+    }
+
+    @Override
+    public void forEach(BiConsumer<? super BlockVector3, ? super BaseBlock> action) {
+        maps.forEach((groupKey, m) ->
+            m.forEach((innerKey, block) ->
+                action.accept(reconstructLocation(groupKey, innerKey), block)
+            )
+        );
+    }
+
+    @Override
+    public void replaceAll(BiFunction<? super BlockVector3, ? super BaseBlock, ? extends BaseBlock> function) {
+        maps.forEach((groupKey, m) ->
+            m.replaceAll((innerKey, block) ->
+                function.apply(reconstructLocation(groupKey, innerKey), block)
+            )
+        );
+    }
+
+    @Override
+    public BaseBlock putIfAbsent(BlockVector3 key, BaseBlock value) {
+        return getOrCreateMap(toGroupKey(key)).putIfAbsent(toInnerKey(key), value);
+    }
+
+    @Override
+    public boolean remove(Object key, Object value) {
+        BlockVector3 vec = (BlockVector3) key;
+        return cleanlyModifyMap(toGroupKey(vec),
+            map -> map.remove(toInnerKey(vec), value));
+    }
+
+    @Override
+    public boolean replace(BlockVector3 key, BaseBlock oldValue, BaseBlock newValue) {
+        return cleanlyModifyMap(toGroupKey(key),
+            map -> map.replace(toInnerKey(key), oldValue, newValue));
+    }
+
+    @Override
+    public BaseBlock replace(BlockVector3 key, BaseBlock value) {
+        return getOrCreateMap(toGroupKey(key)).replace(toInnerKey(key), value);
+    }
+
+    @Override
+    public BaseBlock computeIfAbsent(BlockVector3 key, Function<? super BlockVector3, ? extends BaseBlock> mappingFunction) {
+        return cleanlyModifyMap(toGroupKey(key),
+            map -> map.computeIfAbsent(toInnerKey(key), ik -> mappingFunction.apply(key)));
+    }
+
+    @Override
+    public BaseBlock computeIfPresent(BlockVector3 key, BiFunction<? super BlockVector3, ? super BaseBlock, ? extends BaseBlock> remappingFunction) {
+        return cleanlyModifyMap(toGroupKey(key),
+            map -> map.computeIfPresent(toInnerKey(key), (ik, block) -> remappingFunction.apply(key, block)));
+    }
+
+    @Override
+    public BaseBlock compute(BlockVector3 key, BiFunction<? super BlockVector3, ? super BaseBlock, ? extends BaseBlock> remappingFunction) {
+        return cleanlyModifyMap(toGroupKey(key),
+            map -> map.compute(toInnerKey(key), (ik, block) -> remappingFunction.apply(key, block)));
+    }
+
+    @Override
+    public BaseBlock merge(BlockVector3 key, BaseBlock value, BiFunction<? super BaseBlock, ? super BaseBlock, ? extends BaseBlock> remappingFunction) {
+        return cleanlyModifyMap(toGroupKey(key),
+            map -> map.merge(toInnerKey(key), value, remappingFunction));
+    }
+
+    @Override
+    public Set<Entry<BlockVector3, BaseBlock>> entrySet() {
+        Set<Entry<BlockVector3, BaseBlock>> es = entrySet;
+        if (es == null) {
+            entrySet = es = new AbstractSet<Entry<BlockVector3, BaseBlock>>() {
+                @Override
+                public Iterator<Entry<BlockVector3, BaseBlock>> iterator() {
+                    return new AbstractIterator<Entry<BlockVector3, BaseBlock>>() {
+
+                        private final ObjectIterator<Long2ObjectMap.Entry<SubBlockMap>> primaryIterator
+                            = Long2ObjectMaps.fastIterator(maps);
+                        private long currentGroupKey;
+                        private ObjectIterator<Int2ObjectMap.Entry<BaseBlock>> secondaryIterator;
+
+                        @Override
+                        protected Entry<BlockVector3, BaseBlock> computeNext() {
+                            if (secondaryIterator == null || !secondaryIterator.hasNext()) {
+                                if (!primaryIterator.hasNext()) {
+                                    return endOfData();
+                                }
+
+                                Long2ObjectMap.Entry<SubBlockMap> next = primaryIterator.next();
+                                currentGroupKey = next.getLongKey();
+                                secondaryIterator = Int2ObjectMaps.fastIterator(next.getValue());
+                            }
+                            Int2ObjectMap.Entry<BaseBlock> next = secondaryIterator.next();
+                            return new LazyEntry(currentGroupKey, next.getIntKey(), next.getValue());
+                        }
+                    };
+                }
+
+                @Override
+                public int size() {
+                    return BlockMap.this.size();
+                }
+            };
+        }
+        return es;
+    }
+
+    private final class LazyEntry implements Map.Entry<BlockVector3, BaseBlock> {
+
+        private final long groupKey;
+        private final int innerKey;
+        private BlockVector3 lazyKey;
+        private BaseBlock value;
+
+        private LazyEntry(long groupKey, int innerKey, BaseBlock value) {
+            this.groupKey = groupKey;
+            this.innerKey = innerKey;
+            this.value = value;
+        }
+
+        @Override
+        public BlockVector3 getKey() {
+            BlockVector3 result = lazyKey;
+            if (result == null) {
+                lazyKey = result = reconstructLocation(groupKey, innerKey);
+            }
+            return result;
+        }
+
+        @Override
+        public BaseBlock getValue() {
+            return value;
+        }
+
+        @Override
+        public BaseBlock setValue(BaseBlock value) {
+            this.value = value;
+            return getOrCreateMap(groupKey).put(innerKey, value);
+        }
+
+        public boolean equals(Object o) {
+            if (!(o instanceof Map.Entry))
+                return false;
+            Map.Entry<?, ?> e = (Map.Entry<?, ?>) o;
+            if (o instanceof LazyEntry) {
+                LazyEntry otherE = (LazyEntry) o;
+                return otherE.groupKey == groupKey
+                    && otherE.innerKey == innerKey
+                    && Objects.equals(value, e.getValue());
+            }
+            return Objects.equals(getKey(), e.getKey()) && Objects.equals(value, e.getValue());
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hashCode(getKey()) ^ Objects.hashCode(value);
+        }
+
+        @Override
+        public String toString() {
+            return getKey() + "=" + getValue();
+        }
+    }
+
+    @Override
+    public boolean containsValue(Object value) {
+        return maps.values().stream().anyMatch(m -> m.containsValue(value));
+    }
+
+    @Override
+    public boolean containsKey(Object key) {
+        BlockVector3 vec = (BlockVector3) key;
+        Map<Integer, BaseBlock> activeMap = maps.get(toGroupKey(vec));
+        if (activeMap == null) {
+            return false;
+        }
+        return activeMap.containsKey(toInnerKey(vec));
+    }
+
+    @Override
+    public BaseBlock get(Object key) {
+        BlockVector3 vec = (BlockVector3) key;
+        Map<Integer, BaseBlock> activeMap = maps.get(toGroupKey(vec));
+        if (activeMap == null) {
+            return null;
+        }
+        return activeMap.get(toInnerKey(vec));
+    }
+
+    @Override
+    public BaseBlock remove(Object key) {
+        BlockVector3 vec = (BlockVector3) key;
+        Map<Integer, BaseBlock> activeMap = maps.get(toGroupKey(vec));
+        if (activeMap == null) {
+            return null;
+        }
+        BaseBlock removed = activeMap.remove(toInnerKey(vec));
+        if (activeMap.isEmpty()) {
+            maps.remove(toGroupKey(vec));
+        }
+        return removed;
+    }
+
+    @Override
+    public void putAll(Map<? extends BlockVector3, ? extends BaseBlock> m) {
+        if (m instanceof BlockMap) {
+            // optimize insertions:
+            ((BlockMap) m).maps.forEach((groupKey, map) ->
+                getOrCreateMap(groupKey).putAll(map)
+            );
+        } else {
+            super.putAll(m);
+        }
+    }
+
+    @Override
+    public void clear() {
+        maps.clear();
+    }
+
+    @Override
+    public int size() {
+        return maps.values().stream().mapToInt(Map::size).sum();
+    }
+
+    // no keySet override, since we can't really optimize it.
+    // we can optimize values access though, by skipping BV construction.
+
+    @Override
+    public Collection<BaseBlock> values() {
+        Collection<BaseBlock> vs = values;
+        if (vs == null) {
+            values = vs = new AbstractCollection<BaseBlock>() {
+                @Override
+                public Iterator<BaseBlock> iterator() {
+                    return maps.values().stream()
+                        .flatMap(m -> m.values().stream())
+                        .iterator();
+                }
+
+                @Override
+                public int size() {
+                    return BlockMap.this.size();
+                }
+            };
+        }
+        return vs;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (o == this) {
+            return true;
+        }
+        if (o instanceof BlockMap) {
+            // optimize by skipping entry translations:
+            return maps.equals(((BlockMap) o).maps);
+        }
+        return super.equals(o);
+    }
+
+    // satisfy checkstyle
+    @Override
+    public int hashCode() {
+        return super.hashCode();
+    }
+}
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/LocatedBlockList.java b/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/LocatedBlockList.java
index c1296e88d..221c3bf5a 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/LocatedBlockList.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/LocatedBlockList.java
@@ -19,71 +19,76 @@
 
 package com.sk89q.worldedit.util.collection;
 
-import static com.google.common.base.Preconditions.checkNotNull;
-
+import com.google.common.collect.Iterators;
+import com.sk89q.worldedit.WorldEdit;
+import com.google.common.collect.Iterators;
+import com.sk89q.worldedit.WorldEdit;
 import com.sk89q.worldedit.math.BlockVector3;
 import com.sk89q.worldedit.util.LocatedBlock;
 import com.sk89q.worldedit.world.block.BaseBlock;
 import com.sk89q.worldedit.world.block.BlockStateHolder;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.Iterator;
-import java.util.LinkedHashMap;
-import java.util.List;
-import java.util.Map;
+
 import javax.annotation.Nullable;
+import java.util.Collection;
+import java.util.Iterator;
+
+import static com.google.common.base.Preconditions.checkNotNull;
 
 /**
  * Wrapper around a list of blocks located in the world.
  */
 public class LocatedBlockList implements Iterable<LocatedBlock> {
 
-    private final Map<BlockVector3, LocatedBlock> map = new LinkedHashMap<>();
+    private final BlockMap blocks = BlockMap.create();
+    private final PositionList order = PositionList.create(
+        WorldEdit.getInstance().getConfiguration().extendedYLimit
+    );
 
     public LocatedBlockList() {
     }
 
     public LocatedBlockList(Collection<? extends LocatedBlock> collection) {
         for (LocatedBlock locatedBlock : collection) {
-            map.put(locatedBlock.getLocation(), locatedBlock);
+            add(locatedBlock.getLocation(), locatedBlock.getBlock());
         }
     }
 
     public void add(LocatedBlock setBlockCall) {
         checkNotNull(setBlockCall);
-        map.put(setBlockCall.getLocation(), setBlockCall);
+        add(setBlockCall.getLocation(), setBlockCall.getBlock());
     }
 
     public <B extends BlockStateHolder<B>> void add(BlockVector3 location, B block) {
-        add(new LocatedBlock(location, block.toBaseBlock()));
+        blocks.put(location, block.toBaseBlock());
+        order.add(location);
     }
 
     public boolean containsLocation(BlockVector3 location) {
-        return map.containsKey(location);
+        return blocks.containsKey(location);
     }
 
     public @Nullable BaseBlock get(BlockVector3 location) {
-        return map.get(location).getBlock();
+        return blocks.get(location);
     }
 
     public int size() {
-        return map.size();
+        return order.size();
     }
 
     public void clear() {
-        map.clear();
+        blocks.clear();
+        order.clear();
     }
 
     @Override
     public Iterator<LocatedBlock> iterator() {
-        return map.values().iterator();
+        return Iterators.transform(order.iterator(), position ->
+            new LocatedBlock(position, blocks.get(position)));
     }
 
     public Iterator<LocatedBlock> reverseIterator() {
-        List<LocatedBlock> data = new ArrayList<>(map.values());
-        Collections.reverse(data);
-        return data.iterator();
+        return Iterators.transform(order.reverseIterator(), position ->
+            new LocatedBlock(position, blocks.get(position)));
     }
 
 }
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/LongPositionList.java b/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/LongPositionList.java
new file mode 100644
index 000000000..8d5c0b72a
--- /dev/null
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/LongPositionList.java
@@ -0,0 +1,91 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.collection;
+
+import com.google.common.collect.AbstractIterator;
+import com.sk89q.worldedit.math.BlockVector3;
+import it.unimi.dsi.fastutil.longs.LongArrayList;
+import it.unimi.dsi.fastutil.longs.LongList;
+import it.unimi.dsi.fastutil.longs.LongListIterator;
+
+import java.util.Iterator;
+import java.util.function.Predicate;
+import java.util.function.ToLongFunction;
+
+class LongPositionList implements PositionList {
+
+    private final LongList delegate = new LongArrayList();
+
+    @Override
+    public BlockVector3 get(int index) {
+        return BlockVector3.fromLongPackedForm(delegate.getLong(index));
+    }
+
+    @Override
+    public void add(BlockVector3 vector) {
+        delegate.add(vector.toLongPackedForm());
+    }
+
+    @Override
+    public int size() {
+        return delegate.size();
+    }
+
+    @Override
+    public void clear() {
+        delegate.clear();
+    }
+
+    @Override
+    public Iterator<BlockVector3> iterator() {
+        return new PositionIterator(delegate.iterator(),
+            LongListIterator::hasNext,
+            LongListIterator::nextLong);
+    }
+
+    @Override
+    public Iterator<BlockVector3> reverseIterator() {
+        return new PositionIterator(delegate.listIterator(size()),
+            LongListIterator::hasPrevious,
+            LongListIterator::previousLong);
+    }
+
+    private static final class PositionIterator extends AbstractIterator<BlockVector3> {
+
+        private final LongListIterator iterator;
+        private final Predicate<LongListIterator> hasNext;
+        private final ToLongFunction<LongListIterator> next;
+
+        private PositionIterator(LongListIterator iterator,
+                                 Predicate<LongListIterator> hasNext,
+                                 ToLongFunction<LongListIterator> next) {
+            this.iterator = iterator;
+            this.hasNext = hasNext;
+            this.next = next;
+        }
+
+        @Override
+        protected BlockVector3 computeNext() {
+            return hasNext.test(iterator)
+                ? BlockVector3.fromLongPackedForm(next.applyAsLong(iterator))
+                : endOfData();
+        }
+    }
+}
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/PositionList.java b/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/PositionList.java
new file mode 100644
index 000000000..793f0fef3
--- /dev/null
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/PositionList.java
@@ -0,0 +1,47 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.collection;
+
+import com.sk89q.worldedit.math.BlockVector3;
+
+import java.util.Iterator;
+
+interface PositionList {
+
+    static PositionList create(boolean extendedYLimit) {
+        if (extendedYLimit) {
+            return new VectorPositionList();
+        }
+        return new LongPositionList();
+    }
+
+    BlockVector3 get(int index);
+
+    void add(BlockVector3 vector);
+
+    int size();
+
+    void clear();
+
+    Iterator<BlockVector3> iterator();
+
+    Iterator<BlockVector3> reverseIterator();
+
+}
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/SubBlockMap.java b/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/SubBlockMap.java
new file mode 100644
index 000000000..440f52eee
--- /dev/null
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/SubBlockMap.java
@@ -0,0 +1,194 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.collection;
+
+import com.sk89q.worldedit.internal.block.BlockStateIdAccess;
+import com.sk89q.worldedit.world.block.BaseBlock;
+import com.sk89q.worldedit.world.block.BlockState;
+import it.unimi.dsi.fastutil.ints.AbstractInt2ObjectMap;
+import it.unimi.dsi.fastutil.ints.Int2IntMap;
+import it.unimi.dsi.fastutil.ints.Int2IntMaps;
+import it.unimi.dsi.fastutil.ints.Int2IntOpenHashMap;
+import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
+import it.unimi.dsi.fastutil.ints.Int2ObjectMaps;
+import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
+import it.unimi.dsi.fastutil.objects.AbstractObjectSet;
+import it.unimi.dsi.fastutil.objects.ObjectIterator;
+import it.unimi.dsi.fastutil.objects.ObjectSet;
+
+import java.util.NoSuchElementException;
+import java.util.function.BiFunction;
+
+/**
+ * Int-to-BaseBlock map, but with optimizations for common cases.
+ */
+class SubBlockMap extends AbstractInt2ObjectMap<BaseBlock> {
+
+    private static boolean hasInt(BlockState b) {
+        return BlockStateIdAccess.getBlockStateId(b).isPresent();
+    }
+
+    private static boolean isUncommon(BaseBlock block) {
+        return block.hasNbtData() || !hasInt(block.toImmutableState());
+    }
+
+    private static int assumeAsInt(BlockState b) {
+        return BlockStateIdAccess.getBlockStateId(b)
+            .orElseThrow(() -> new IllegalStateException("Block state " + b + " did not have an ID"));
+    }
+
+    private static BaseBlock assumeAsBlock(int id) {
+        if (id == Integer.MIN_VALUE) {
+            return null;
+        }
+        BlockState state = BlockStateIdAccess.getBlockStateById(id);
+        if (state == null) {
+            throw new IllegalStateException("No state for ID " + id);
+        }
+        return state.toBaseBlock();
+    }
+
+    static final SubBlockMap EMPTY = new SubBlockMap();
+
+    private final Int2IntMap commonMap = new Int2IntOpenHashMap(64, 1f);
+    private final Int2ObjectMap<BaseBlock> uncommonMap = new Int2ObjectOpenHashMap<>(1, 1f);
+
+    {
+        commonMap.defaultReturnValue(Integer.MIN_VALUE);
+    }
+
+    @Override
+    public int size() {
+        return commonMap.size() + uncommonMap.size();
+    }
+
+    @Override
+    public ObjectSet<Entry<BaseBlock>> int2ObjectEntrySet() {
+        return new AbstractObjectSet<Entry<BaseBlock>>() {
+            @Override
+            public ObjectIterator<Entry<BaseBlock>> iterator() {
+                return new ObjectIterator<Entry<BaseBlock>>() {
+
+                    private final ObjectIterator<Int2IntMap.Entry> commonIter
+                        = Int2IntMaps.fastIterator(commonMap);
+                    private final ObjectIterator<Int2ObjectMap.Entry<BaseBlock>> uncommonIter
+                        = Int2ObjectMaps.fastIterator(uncommonMap);
+
+                    @Override
+                    public boolean hasNext() {
+                        return commonIter.hasNext() || uncommonIter.hasNext();
+                    }
+
+                    @Override
+                    public Entry<BaseBlock> next() {
+                        if (commonIter.hasNext()) {
+                            Int2IntMap.Entry e = commonIter.next();
+                            return new BasicEntry<>(
+                                e.getIntKey(), assumeAsBlock(e.getIntValue())
+                            );
+                        }
+                        if (uncommonIter.hasNext()) {
+                            return uncommonIter.next();
+                        }
+                        throw new NoSuchElementException();
+                    }
+                };
+            }
+
+            @Override
+            public int size() {
+                return SubBlockMap.this.size();
+            }
+        };
+    }
+
+    @Override
+    public BaseBlock get(int key) {
+        int oldId = commonMap.get(key);
+        if (oldId == Integer.MIN_VALUE) {
+            return uncommonMap.get(key);
+        }
+        return assumeAsBlock(oldId);
+    }
+
+    @Override
+    public boolean containsKey(int k) {
+        return commonMap.containsKey(k) || uncommonMap.containsKey(k);
+    }
+
+    @Override
+    public boolean containsValue(Object v) {
+        BaseBlock block = (BaseBlock) v;
+        if (isUncommon(block)) {
+            return uncommonMap.containsValue(block);
+        }
+        return commonMap.containsValue(assumeAsInt(block.toImmutableState()));
+    }
+
+    @Override
+    public BaseBlock put(int key, BaseBlock value) {
+        if (isUncommon(value)) {
+            BaseBlock old = uncommonMap.put(key, value);
+            if (old == null) {
+                // ensure common doesn't have the entry too
+                int oldId = commonMap.remove(key);
+                return assumeAsBlock(oldId);
+            }
+            return old;
+        }
+        int oldId = commonMap.put(key, assumeAsInt(value.toImmutableState()));
+        return assumeAsBlock(oldId);
+    }
+
+    @Override
+    public BaseBlock remove(int key) {
+        int removed = commonMap.remove(key);
+        if (removed == Integer.MIN_VALUE) {
+            return uncommonMap.remove(key);
+        }
+        return assumeAsBlock(removed);
+    }
+
+    @Override
+    public void replaceAll(BiFunction<? super Integer, ? super BaseBlock, ? extends BaseBlock> function) {
+        for (ObjectIterator<Int2IntMap.Entry> iter = Int2IntMaps.fastIterator(commonMap);
+             iter.hasNext(); ) {
+            Int2IntMap.Entry next = iter.next();
+            BaseBlock value = function.apply(next.getIntKey(), assumeAsBlock(next.getIntValue()));
+            if (isUncommon(value)) {
+                uncommonMap.put(next.getIntKey(), value);
+                iter.remove();
+            } else {
+                next.setValue(assumeAsInt(value.toImmutableState()));
+            }
+        }
+        for (ObjectIterator<Int2ObjectMap.Entry<BaseBlock>> iter = Int2ObjectMaps.fastIterator(uncommonMap);
+             iter.hasNext(); ) {
+            Int2ObjectMap.Entry<BaseBlock> next = iter.next();
+            BaseBlock value = function.apply(next.getIntKey(), next.getValue());
+            if (isUncommon(value)) {
+                next.setValue(value);
+            } else {
+                commonMap.put(next.getIntKey(), assumeAsInt(value.toImmutableState()));
+                iter.remove();
+            }
+        }
+    }
+}
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/VectorPositionList.java b/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/VectorPositionList.java
new file mode 100644
index 000000000..6c8d27ddf
--- /dev/null
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/util/collection/VectorPositionList.java
@@ -0,0 +1,98 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.collection;
+
+import com.google.common.collect.AbstractIterator;
+import com.sk89q.worldedit.math.BlockVector3;
+import it.unimi.dsi.fastutil.ints.IntArrayList;
+import it.unimi.dsi.fastutil.ints.IntIterator;
+import it.unimi.dsi.fastutil.ints.IntList;
+import it.unimi.dsi.fastutil.ints.IntListIterator;
+
+import java.util.Iterator;
+
+class VectorPositionList implements PositionList {
+
+    private final IntList delegate = new IntArrayList();
+
+    @Override
+    public BlockVector3 get(int index) {
+        int ri = index * 3;
+        return BlockVector3.at(
+            delegate.getInt(ri),
+            delegate.getInt(ri + 1),
+            delegate.getInt(ri + 2));
+    }
+
+    @Override
+    public void add(BlockVector3 vector) {
+        delegate.add(vector.getX());
+        delegate.add(vector.getY());
+        delegate.add(vector.getZ());
+    }
+
+    @Override
+    public int size() {
+        return delegate.size();
+    }
+
+    @Override
+    public void clear() {
+        delegate.clear();
+    }
+
+    @Override
+    public Iterator<BlockVector3> iterator() {
+        return new AbstractIterator<BlockVector3>() {
+
+            private final IntIterator iterator = delegate.iterator();
+
+            @Override
+            protected BlockVector3 computeNext() {
+                if (!iterator.hasNext()) {
+                    return endOfData();
+                }
+                return BlockVector3.at(
+                    iterator.nextInt(),
+                    iterator.nextInt(),
+                    iterator.nextInt());
+            }
+        };
+    }
+
+    @Override
+    public Iterator<BlockVector3> reverseIterator() {
+        return new AbstractIterator<BlockVector3>() {
+
+            private final IntListIterator iterator = delegate.listIterator(delegate.size());
+
+            @Override
+            protected BlockVector3 computeNext() {
+                if (!iterator.hasPrevious()) {
+                    return endOfData();
+                }
+                return BlockVector3.at(
+                    iterator.previousInt(),
+                    iterator.previousInt(),
+                    iterator.previousInt());
+            }
+        };
+    }
+}
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/util/concurrency/LazyReference.java b/worldedit-core/src/main/java/com/sk89q/worldedit/util/concurrency/LazyReference.java
new file mode 100644
index 000000000..720ca0161
--- /dev/null
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/util/concurrency/LazyReference.java
@@ -0,0 +1,75 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.util.concurrency;
+
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+import java.util.function.Supplier;
+
+/**
+ * Thread-safe lazy reference.
+ */
+public class LazyReference<T> {
+
+    public static <T> LazyReference<T> from(Supplier<T> valueComputation) {
+        return new LazyReference<>(valueComputation);
+    }
+
+    // Memory saving technique: hold the computation info in the same reference field that we'll
+    // put the value into, so the memory possibly retained by those parts is GC'able as soon as
+    // it's no longer needed.
+
+    private static final class RefInfo<T> {
+        private final Lock lock = new ReentrantLock();
+        private final Supplier<T> valueComputation;
+
+        private RefInfo(Supplier<T> valueComputation) {
+            this.valueComputation = valueComputation;
+        }
+    }
+
+    private Object value;
+
+    private LazyReference(Supplier<T> valueComputation) {
+        this.value = new RefInfo<>(valueComputation);
+    }
+
+    // casts are safe, value is either RefInfo or T
+    @SuppressWarnings("unchecked")
+    public T getValue() {
+        Object v = value;
+        if (!(v instanceof RefInfo)) {
+            return (T) v;
+        }
+        RefInfo<T> refInfo = (RefInfo<T>) v;
+        refInfo.lock.lock();
+        try {
+            v = value;
+            if (!(v instanceof RefInfo)) {
+                return (T) v;
+            }
+            value = v = refInfo.valueComputation.get();
+            return (T) v;
+        } finally {
+            refInfo.lock.unlock();
+        }
+    }
+
+}
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/world/registry/LegacyMapper.java b/worldedit-core/src/main/java/com/sk89q/worldedit/world/registry/LegacyMapper.java
index cd9d1db06..0c4feae79 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/world/registry/LegacyMapper.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/world/registry/LegacyMapper.java
@@ -104,7 +104,7 @@ public final class LegacyMapper {
                 if (type.hasProperty(PropertyKey.WATERLOGGED)) {
                     blockState = blockState.with(PropertyKey.WATERLOGGED, false);
                 }
-                int combinedId = getCombinedId(blockEntry.getKey());
+                Integer combinedId = getCombinedId(blockEntry.getKey());
                 blockArr[combinedId] = blockState.getInternalId();
 
                 blockStateToLegacyId4Data.put(blockState.getInternalId(), (Integer) combinedId);
@@ -221,7 +221,7 @@ public final class LegacyMapper {
     }
 
     public void register(int id, int data, BlockStateHolder state) {
-        int combinedId = ((id << 4) + data);
+        Integer combinedId = ((id << 4) + data);
         extraId4DataToStateId.put(combinedId, (Integer) state.getInternalId());
         blockStateToLegacyId4Data.putIfAbsent(state.getInternalId(), combinedId);
     }
diff --git a/worldedit-core/src/main/java/net/jpountz/util/UnsafeUtils.java b/worldedit-core/src/main/java/net/jpountz/util/UnsafeUtils.java
index 665616011..b66bfce6b 100644
--- a/worldedit-core/src/main/java/net/jpountz/util/UnsafeUtils.java
+++ b/worldedit-core/src/main/java/net/jpountz/util/UnsafeUtils.java
@@ -43,11 +43,7 @@ public enum UnsafeUtils {
             INT_ARRAY_SCALE = UNSAFE.arrayIndexScale(int[].class);
             SHORT_ARRAY_OFFSET = UNSAFE.arrayBaseOffset(short[].class);
             SHORT_ARRAY_SCALE = UNSAFE.arrayIndexScale(short[].class);
-        } catch (IllegalAccessException e) {
-            throw new ExceptionInInitializerError("Cannot access Unsafe");
-        } catch (NoSuchFieldException e) {
-            throw new ExceptionInInitializerError("Cannot access Unsafe");
-        } catch (SecurityException e) {
+        } catch (IllegalAccessException | NoSuchFieldException | SecurityException e) {
             throw new ExceptionInInitializerError("Cannot access Unsafe");
         }
     }
diff --git a/worldedit-core/src/test/java/com/sk89q/worldedit/internal/expression/ExpressionTest.java b/worldedit-core/src/test/java/com/sk89q/worldedit/internal/expression/ExpressionTest.java
index 15d4f8225..de9cce3cc 100644
--- a/worldedit-core/src/test/java/com/sk89q/worldedit/internal/expression/ExpressionTest.java
+++ b/worldedit-core/src/test/java/com/sk89q/worldedit/internal/expression/ExpressionTest.java
@@ -19,16 +19,6 @@
 
 package com.sk89q.worldedit.internal.expression;
 
-import static java.lang.Math.atan2;
-import static java.lang.Math.sin;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
-
-import org.junit.Before;
-import org.junit.Test;
-import org.mockito.Mockito;
-
 import com.sk89q.worldedit.LocalConfiguration;
 import com.sk89q.worldedit.WorldEdit;
 import com.sk89q.worldedit.extension.platform.Platform;
@@ -36,17 +26,27 @@ import com.sk89q.worldedit.internal.expression.lexer.LexerException;
 import com.sk89q.worldedit.internal.expression.parser.ParserException;
 import com.sk89q.worldedit.internal.expression.runtime.EvaluationException;
 import com.sk89q.worldedit.internal.expression.runtime.ExpressionEnvironment;
+import com.sk89q.worldedit.internal.expression.runtime.ExpressionTimeoutException;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
 import static java.lang.Math.atan2;
 import static java.lang.Math.sin;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.assertAll;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
 
 public class ExpressionTest {
-    @Before
+
+    private Platform mockPlat = mock(Platform.class);
+
+    @BeforeEach
     public void setup() {
-        Platform mockPlat = Mockito.mock(Platform.class);
-        Mockito.when(mockPlat.getConfiguration()).thenReturn(new LocalConfiguration() {
+        when(mockPlat.getConfiguration()).thenReturn(new LocalConfiguration() {
             @Override
             public void load() {
             }
@@ -54,9 +54,14 @@ public class ExpressionTest {
         WorldEdit.getInstance().getPlatformManager().register(mockPlat);
     }
 
+    @AfterEach
+    public void tearDown() {
+        WorldEdit.getInstance().getPlatformManager().unregister(mockPlat);
+    }
+
     @Test
     public void testEvaluate() throws ExpressionException {
-        // check 
+        // check
         assertEquals(1 - 2 + 3, simpleEval("1 - 2 + 3"), 0);
 
         // check unary ops
@@ -73,56 +78,46 @@ public class ExpressionTest {
     }
 
     @Test
-    public void testErrors() throws ExpressionException {
-        // test lexer errors
-        try {
-            compile("#");
-            fail("Error expected");
-        } catch (LexerException e) {
-            assertEquals("Error position", 0, e.getPosition());
-        }
-
-        // test parser errors
-        try {
-            compile("x");
-            fail("Error expected");
-        } catch (ParserException e) {
-            assertEquals("Error position", 0, e.getPosition());
-        }
-        try {
-            compile("x()");
-            fail("Error expected");
-        } catch (ParserException e) {
-            assertEquals("Error position", 0, e.getPosition());
-        }
-        try {
-            compile("(");
-            fail("Error expected");
-        } catch (ParserException ignored) {}
-        try {
-            compile("x(");
-            fail("Error expected");
-        } catch (ParserException ignored) {}
-
-        // test overloader errors
-        try {
-            compile("atan2(1)");
-            fail("Error expected");
-        } catch (ParserException e) {
-            assertEquals("Error position", 0, e.getPosition());
-        }
-        try {
-            compile("atan2(1, 2, 3)");
-            fail("Error expected");
-        } catch (ParserException e) {
-            assertEquals("Error position", 0, e.getPosition());
-        }
-        try {
-            compile("rotate(1, 2, 3)");
-            fail("Error expected");
-        } catch (ParserException e) {
-            assertEquals("Error position", 0, e.getPosition());
-        }
+    public void testErrors() {
+        assertAll(
+            // test lexer errors
+            () -> {
+                LexerException e = assertThrows(LexerException.class,
+                    () -> compile("#"));
+                assertEquals(0, e.getPosition(), "Error position");
+            },
+            // test parser errors
+            () -> {
+                ParserException e = assertThrows(ParserException.class,
+                    () -> compile("x"));
+                assertEquals(0, e.getPosition(), "Error position");
+            },
+            () -> {
+                ParserException e = assertThrows(ParserException.class,
+                    () -> compile("x()"));
+                assertEquals(0, e.getPosition(), "Error position");
+            },
+            () -> assertThrows(ParserException.class,
+                () -> compile("(")),
+            () -> assertThrows(ParserException.class,
+                () -> compile("x(")),
+            // test overloader errors
+            () -> {
+                ParserException e = assertThrows(ParserException.class,
+                    () -> compile("atan2(1)"));
+                assertEquals(0, e.getPosition(), "Error position");
+            },
+            () -> {
+                ParserException e = assertThrows(ParserException.class,
+                    () -> compile("atan2(1, 2, 3)"));
+                assertEquals(0, e.getPosition(), "Error position");
+            },
+            () -> {
+                ParserException e = assertThrows(ParserException.class,
+                    () -> compile("rotate(1, 2, 3)"));
+                assertEquals(0, e.getPosition(), "Error position");
+            }
+        );
     }
 
     @Test
@@ -186,13 +181,11 @@ public class ExpressionTest {
     }
 
     @Test
-    public void testTimeout() throws Exception {
-        try {
-            simpleEval("for(i=0;i<256;i++){for(j=0;j<256;j++){for(k=0;k<256;k++){for(l=0;l<256;l++){ln(pi)}}}}");
-            fail("Loop was not stopped.");
-        } catch (EvaluationException e) {
-            assertTrue(e.getMessage().contains("Calculations exceeded time limit"));
-        }
+    public void testTimeout() {
+        ExpressionTimeoutException e = assertThrows(ExpressionTimeoutException.class,
+            () -> simpleEval("for(i=0;i<256;i++){for(j=0;j<256;j++){for(k=0;k<256;k++){for(l=0;l<256;l++){ln(pi)}}}}"),
+            "Loop was not stopped.");
+        assertTrue(e.getMessage().contains("Calculations exceeded time limit"));
     }
 
     private double simpleEval(String expressionString) throws ExpressionException {