diff --git a/worldedit-bukkit/src/main/java/com/fastasyncworldedit/bukkit/FaweBukkit.java b/worldedit-bukkit/src/main/java/com/fastasyncworldedit/bukkit/FaweBukkit.java
index 8aff475d1..3f11d04f6 100644
--- a/worldedit-bukkit/src/main/java/com/fastasyncworldedit/bukkit/FaweBukkit.java
+++ b/worldedit-bukkit/src/main/java/com/fastasyncworldedit/bukkit/FaweBukkit.java
@@ -84,7 +84,7 @@ public class FaweBukkit implements IFawe, Listener {
             Bukkit.getServer().shutdown();
         }
 
-        chunksStretched = new MinecraftVersion().isEqualOrHigher(MinecraftVersion.NETHER);
+        chunksStretched = new MinecraftVersion().isEqualOrLower(MinecraftVersion.NETHER);
 
         platformAdapter = new NMSAdapter();
 
diff --git a/worldedit-bukkit/src/main/java/com/fastasyncworldedit/bukkit/regions/GriefPreventionFeature.java b/worldedit-bukkit/src/main/java/com/fastasyncworldedit/bukkit/regions/GriefPreventionFeature.java
index 0798cf973..c75349b76 100644
--- a/worldedit-bukkit/src/main/java/com/fastasyncworldedit/bukkit/regions/GriefPreventionFeature.java
+++ b/worldedit-bukkit/src/main/java/com/fastasyncworldedit/bukkit/regions/GriefPreventionFeature.java
@@ -1,7 +1,9 @@
 package com.fastasyncworldedit.bukkit.regions;
 
 import com.fastasyncworldedit.core.regions.FaweMask;
+import com.sk89q.worldedit.WorldEdit;
 import com.sk89q.worldedit.bukkit.BukkitAdapter;
+import com.sk89q.worldedit.extension.platform.Capability;
 import com.sk89q.worldedit.internal.util.LogManagerCompat;
 import com.sk89q.worldedit.math.BlockVector3;
 import com.sk89q.worldedit.regions.CuboidRegion;
@@ -38,12 +40,12 @@ public class GriefPreventionFeature extends BukkitMaskManager implements Listene
                 claim.getGreaterBoundaryCorner().getBlockX();
                 final BlockVector3 pos1 = BlockVector3.at(
                         claim.getLesserBoundaryCorner().getBlockX(),
-                        0,
+                        player.getWorld().getMinHeight(),
                         claim.getLesserBoundaryCorner().getBlockZ()
                 );
                 final BlockVector3 pos2 = BlockVector3.at(
                         claim.getGreaterBoundaryCorner().getBlockX(),
-                        256,
+                        player.getWorld().getMaxHeight(),
                         claim.getGreaterBoundaryCorner().getBlockZ()
                 );
                 return new FaweMask(new CuboidRegion(pos1, pos2)) {
diff --git a/worldedit-bukkit/src/main/java/com/fastasyncworldedit/bukkit/util/MinecraftVersion.java b/worldedit-bukkit/src/main/java/com/fastasyncworldedit/bukkit/util/MinecraftVersion.java
index cba863428..7715c65e2 100644
--- a/worldedit-bukkit/src/main/java/com/fastasyncworldedit/bukkit/util/MinecraftVersion.java
+++ b/worldedit-bukkit/src/main/java/com/fastasyncworldedit/bukkit/util/MinecraftVersion.java
@@ -12,6 +12,7 @@ public class MinecraftVersion implements Comparable<MinecraftVersion> {
 
     public static final MinecraftVersion NETHER = new MinecraftVersion(1, 16);
     public static final MinecraftVersion CAVES_17 = new MinecraftVersion(1, 17);
+    public static final MinecraftVersion CAVES_18 = new MinecraftVersion(1, 18);
 
     private final int major;
     private final int minor;
diff --git a/worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitServerInterface.java b/worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitServerInterface.java
index 83fc8c889..033790560 100644
--- a/worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitServerInterface.java
+++ b/worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/BukkitServerInterface.java
@@ -19,6 +19,7 @@
 
 package com.sk89q.worldedit.bukkit;
 
+import com.fastasyncworldedit.bukkit.util.MinecraftVersion;
 import com.fastasyncworldedit.core.extent.processor.lighting.RelighterFactory;
 import com.google.common.collect.Sets;
 import com.sk89q.bukkit.util.CommandInfo;
@@ -278,5 +279,15 @@ public class BukkitServerInterface extends AbstractPlatform implements MultiUser
         }
         return this.relighterFactory;
     }
+
+    @Override
+    public int getVersionMinY() {
+        return new MinecraftVersion().isEqualOrLower(MinecraftVersion.CAVES_18) ? -64 : 0;
+    }
+
+    @Override
+    public int getVersionMaxY() {
+        return new MinecraftVersion().isEqualOrLower(MinecraftVersion.CAVES_18) ? 319 : 255;
+    }
     //FAWE end
 }
diff --git a/worldedit-core/src/main/java/com/fastasyncworldedit/core/regions/RegionWrapper.java b/worldedit-core/src/main/java/com/fastasyncworldedit/core/regions/RegionWrapper.java
index a5d38deee..55a39eb21 100644
--- a/worldedit-core/src/main/java/com/fastasyncworldedit/core/regions/RegionWrapper.java
+++ b/worldedit-core/src/main/java/com/fastasyncworldedit/core/regions/RegionWrapper.java
@@ -1,5 +1,7 @@
 package com.fastasyncworldedit.core.regions;
 
+import com.sk89q.worldedit.WorldEdit;
+import com.sk89q.worldedit.extension.platform.Capability;
 import com.sk89q.worldedit.math.BlockVector3;
 import com.sk89q.worldedit.regions.CuboidRegion;
 
@@ -27,7 +29,13 @@ public class RegionWrapper extends CuboidRegion {
      */
     @Deprecated
     public RegionWrapper(final int minX, final int maxX, final int minZ, final int maxZ) {
-        this(minX, maxX, 0, 255, minZ, maxZ);
+        this(minX,
+                maxX,
+                WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMinY(),
+                WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMaxY(),
+                minZ,
+                maxZ
+        );
     }
 
     public RegionWrapper(final int minX, final int maxX, final int minY, final int maxY, final int minZ, final int maxZ) {
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/input/ParserContext.java b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/input/ParserContext.java
index e1f6cdca1..30ac850a5 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/input/ParserContext.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/input/ParserContext.java
@@ -21,8 +21,10 @@ package com.sk89q.worldedit.extension.input;
 
 import com.fastasyncworldedit.core.configuration.Caption;
 import com.sk89q.worldedit.LocalSession;
+import com.sk89q.worldedit.WorldEdit;
 import com.sk89q.worldedit.extension.factory.MaskFactory;
 import com.sk89q.worldedit.extension.platform.Actor;
+import com.sk89q.worldedit.extension.platform.Capability;
 import com.sk89q.worldedit.extension.platform.Locatable;
 import com.sk89q.worldedit.extent.Extent;
 import com.sk89q.worldedit.world.World;
@@ -303,8 +305,8 @@ public class ParserContext {
             minY = extent.getMinY();
             maxY = extent.getMaxY();
         } else {
-            minY = 0;
-            maxY = 255;
+            minY = WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMinY();
+            maxY = WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMaxY();
         }
 
         return minY;
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/platform/Platform.java b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/platform/Platform.java
index abb84c3fe..dd4012ebe 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/extension/platform/Platform.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/extension/platform/Platform.java
@@ -22,6 +22,7 @@ package com.sk89q.worldedit.extension.platform;
 import com.fastasyncworldedit.core.extent.processor.lighting.Relighter;
 import com.fastasyncworldedit.core.extent.processor.lighting.RelighterFactory;
 import com.sk89q.worldedit.LocalConfiguration;
+import com.sk89q.worldedit.WorldEdit;
 import com.sk89q.worldedit.entity.Player;
 import com.sk89q.worldedit.internal.util.NonAbstractForCompatibility;
 import com.sk89q.worldedit.registry.Keyed;
@@ -235,5 +236,15 @@ public interface Platform extends Keyed {
      */
     @Nonnull
     RelighterFactory getRelighterFactory();
+
+    /**
+     * Get the default minimum Y value of worlds based on Minecraft version (inclusive).
+     */
+    int getVersionMinY();
+
+    /**
+     * Get the default maximum Y value of worlds based on Minecraft version (inclusive).
+     */
+    int getVersionMaxY();
     //FAWE end
 }
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/extent/OutputExtent.java b/worldedit-core/src/main/java/com/sk89q/worldedit/extent/OutputExtent.java
index ffe880557..df2e07723 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/extent/OutputExtent.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/extent/OutputExtent.java
@@ -22,7 +22,9 @@ package com.sk89q.worldedit.extent;
 import com.fastasyncworldedit.core.extent.processor.heightmap.HeightMapType;
 import com.fastasyncworldedit.core.math.MutableBlockVector3;
 import com.sk89q.jnbt.CompoundTag;
+import com.sk89q.worldedit.WorldEdit;
 import com.sk89q.worldedit.WorldEditException;
+import com.sk89q.worldedit.extension.platform.Capability;
 import com.sk89q.worldedit.function.operation.Operation;
 import com.sk89q.worldedit.internal.util.DeprecationUtil;
 import com.sk89q.worldedit.internal.util.NonAbstractForCompatibility;
@@ -95,7 +97,9 @@ public interface OutputExtent {
     @Deprecated
     default boolean setBiome(BlockVector2 position, BiomeType biome) {
         boolean result = false;
-        for (int y = 0; y < 256; y++) {
+        int minY = WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMinY();
+        int maxY = WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMaxY();
+        for (int y = minY; y < maxY; y++) {
             result |= setBiome(position.toBlockVector3().mutY(y), biome);
         }
         return result;
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/function/mask/OffsetMask.java b/worldedit-core/src/main/java/com/sk89q/worldedit/function/mask/OffsetMask.java
index 91e92964f..2f83000b8 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/function/mask/OffsetMask.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/function/mask/OffsetMask.java
@@ -19,6 +19,8 @@
 
 package com.sk89q.worldedit.function.mask;
 
+import com.sk89q.worldedit.WorldEdit;
+import com.sk89q.worldedit.extension.platform.Capability;
 import com.sk89q.worldedit.math.BlockVector3;
 
 import javax.annotation.Nullable;
@@ -47,7 +49,10 @@ public class OffsetMask extends AbstractMask {
      */
     @Deprecated
     public OffsetMask(Mask mask, BlockVector3 offset) {
-        this(mask, offset, 0, 255);
+        this(mask, offset,
+                WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMinY(),
+                WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMaxY()
+        );
     }
 
     /**
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/BreadthFirstSearch.java b/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/BreadthFirstSearch.java
index 8decb381a..baab0e4c5 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/BreadthFirstSearch.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/BreadthFirstSearch.java
@@ -28,7 +28,9 @@ import com.fastasyncworldedit.core.queue.implementation.SingleThreadQueueExtent;
 import com.fastasyncworldedit.core.util.ExtentTraverser;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Sets;
+import com.sk89q.worldedit.WorldEdit;
 import com.sk89q.worldedit.WorldEditException;
+import com.sk89q.worldedit.extension.platform.Capability;
 import com.sk89q.worldedit.extent.Extent;
 import com.sk89q.worldedit.function.RegionFunction;
 import com.sk89q.worldedit.function.operation.Operation;
@@ -110,7 +112,10 @@ public abstract class BreadthFirstSearch implements Operation {
      */
     public BreadthFirstSearch(RegionFunction function) {
         //FAWE start - int depth, min/max y
-        this(function, Integer.MAX_VALUE, 0, 255, null);
+        this(function, Integer.MAX_VALUE,
+                WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMinY(),
+                WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMaxY(), null
+        );
     }
 
     //FAWE start - int depth, min/max y, preloading
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/DownwardVisitor.java b/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/DownwardVisitor.java
index 7ea7f99e6..0ebeacce0 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/DownwardVisitor.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/DownwardVisitor.java
@@ -19,6 +19,8 @@
 
 package com.sk89q.worldedit.function.visitor;
 
+import com.sk89q.worldedit.WorldEdit;
+import com.sk89q.worldedit.extension.platform.Capability;
 import com.sk89q.worldedit.extent.Extent;
 import com.sk89q.worldedit.function.RegionFunction;
 import com.sk89q.worldedit.function.mask.Mask;
@@ -48,7 +50,10 @@ public class DownwardVisitor extends RecursiveVisitor {
     @Deprecated
     public DownwardVisitor(Mask mask, RegionFunction function, int baseY) {
         //FAWE start - int depth, min/max y
-        this(mask, function, baseY, Integer.MAX_VALUE, 0, 255, null);
+        this(mask, function, baseY, Integer.MAX_VALUE, WorldEdit
+                        .getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMinY(),
+                WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMaxY(), null
+        );
         //FAWE end
     }
 
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/NonRisingVisitor.java b/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/NonRisingVisitor.java
index c4dedc1b3..d206d84fe 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/NonRisingVisitor.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/NonRisingVisitor.java
@@ -19,6 +19,8 @@
 
 package com.sk89q.worldedit.function.visitor;
 
+import com.sk89q.worldedit.WorldEdit;
+import com.sk89q.worldedit.extension.platform.Capability;
 import com.sk89q.worldedit.extent.Extent;
 import com.sk89q.worldedit.function.RegionFunction;
 import com.sk89q.worldedit.function.mask.Mask;
@@ -39,7 +41,10 @@ public class NonRisingVisitor extends RecursiveVisitor {
     @Deprecated
     public NonRisingVisitor(Mask mask, RegionFunction function) {
         //FAWE start - int depth, y min/max
-        this(mask, function, Integer.MAX_VALUE, 0, 255, null);
+        this(mask, function, Integer.MAX_VALUE, WorldEdit
+                        .getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMinY(),
+                WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMaxY(), null
+        );
         //FAWE end
     }
 
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/RecursiveVisitor.java b/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/RecursiveVisitor.java
index 861210a46..c96e4b063 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/RecursiveVisitor.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/function/visitor/RecursiveVisitor.java
@@ -19,6 +19,8 @@
 
 package com.sk89q.worldedit.function.visitor;
 
+import com.sk89q.worldedit.WorldEdit;
+import com.sk89q.worldedit.extension.platform.Capability;
 import com.sk89q.worldedit.extent.Extent;
 import com.sk89q.worldedit.function.RegionFunction;
 import com.sk89q.worldedit.function.mask.Mask;
@@ -41,7 +43,10 @@ public class RecursiveVisitor extends BreadthFirstSearch {
      * @param function the function
      */
     public RecursiveVisitor(Mask mask, RegionFunction function) {
-        this(mask, function, Integer.MAX_VALUE, 0, 255, null);
+        this(mask, function, Integer.MAX_VALUE, WorldEdit
+                        .getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMinY(),
+                WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMaxY(), null
+        );
         //FAWE end
     }
 
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/regions/AbstractRegion.java b/worldedit-core/src/main/java/com/sk89q/worldedit/regions/AbstractRegion.java
index 2768f914b..bfcb40400 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/regions/AbstractRegion.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/regions/AbstractRegion.java
@@ -20,6 +20,8 @@
 package com.sk89q.worldedit.regions;
 
 import com.fastasyncworldedit.core.math.BlockVectorSet;
+import com.sk89q.worldedit.WorldEdit;
+import com.sk89q.worldedit.extension.platform.Capability;
 import com.sk89q.worldedit.math.BlockVector2;
 import com.sk89q.worldedit.math.BlockVector3;
 import com.sk89q.worldedit.math.Vector3;
@@ -221,14 +223,22 @@ public abstract class AbstractRegion extends AbstractSet<BlockVector3> implement
     // Sub-class utilities
 
     protected final int getWorldMinY() {
-        //FAWE start > Integer.MIN_VALUE -> 0 (to avoid crazy for loops...) TODO: See if there's a way to find a "server default"
-        return world == null ? 0 : world.getMinY();
+        //FAWE start > Server default based on version
+        return world == null ? WorldEdit
+                .getInstance()
+                .getPlatformManager()
+                .queryCapability(Capability.WORLD_EDITING)
+                .getVersionMinY() : world.getMinY();
         //FAWE end
     }
 
     protected final int getWorldMaxY() {
-        //FAWE start > Integer.MAX_VALUE -> 255 (to avoid crazy for loops...) TODO: See if there's a way to find a "server default"
-        return world == null ? 255 : world.getMaxY();
+        //FAWE start > Server default based on version
+        return world == null ? WorldEdit
+                .getInstance()
+                .getPlatformManager()
+                .queryCapability(Capability.WORLD_EDITING)
+                .getVersionMaxY() : world.getMaxY();
         //FAWE end
     }
 
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/regions/Region.java b/worldedit-core/src/main/java/com/sk89q/worldedit/regions/Region.java
index 8515b8952..240f039fb 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/regions/Region.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/regions/Region.java
@@ -29,6 +29,8 @@ import com.fastasyncworldedit.core.queue.IBatchProcessor;
 import com.fastasyncworldedit.core.queue.IChunk;
 import com.fastasyncworldedit.core.queue.IChunkGet;
 import com.fastasyncworldedit.core.queue.IChunkSet;
+import com.sk89q.worldedit.WorldEdit;
+import com.sk89q.worldedit.extension.platform.Capability;
 import com.sk89q.worldedit.extent.Extent;
 import com.sk89q.worldedit.internal.util.DeprecationUtil;
 import com.sk89q.worldedit.internal.util.NonAbstractForCompatibility;
@@ -226,7 +228,18 @@ public interface Region extends Iterable<BlockVector3>, Cloneable, IBatchProcess
         BlockVector3 pos1 = getMinimumPoint();
         BlockVector3 pos2 = getMaximumPoint();
         return pos1.getBlockX() == Integer.MIN_VALUE && pos1.getBlockZ() == Integer.MIN_VALUE && pos2.getBlockX() == Integer.MAX_VALUE && pos2
-                .getBlockZ() == Integer.MAX_VALUE && pos1.getBlockY() <= 0 && pos2.getBlockY() >= 255;
+                .getBlockZ() == Integer.MAX_VALUE
+                && pos1.getBlockY() <= WorldEdit
+                .getInstance()
+                .getPlatformManager()
+                .queryCapability(
+                        Capability.WORLD_EDITING)
+                .getVersionMinY()
+                && pos2.getBlockY() >= WorldEdit
+                .getInstance()
+                .getPlatformManager()
+                .queryCapability(Capability.WORLD_EDITING)
+                .getVersionMaxY();
     }
 
     default int getMinimumY() {
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/world/AbstractWorld.java b/worldedit-core/src/main/java/com/sk89q/worldedit/world/AbstractWorld.java
index 1f498a873..bee63181f 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/world/AbstractWorld.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/world/AbstractWorld.java
@@ -20,9 +20,11 @@
 package com.sk89q.worldedit.world;
 
 import com.fastasyncworldedit.core.function.mask.BlockMaskBuilder;
+import com.sk89q.worldedit.WorldEdit;
 import com.sk89q.worldedit.WorldEditException;
 import com.sk89q.worldedit.blocks.BaseItem;
 import com.sk89q.worldedit.blocks.BaseItemStack;
+import com.sk89q.worldedit.extension.platform.Capability;
 import com.sk89q.worldedit.extension.platform.Platform;
 import com.sk89q.worldedit.function.mask.Mask;
 import com.sk89q.worldedit.function.operation.Operation;
@@ -66,12 +68,12 @@ public abstract class AbstractWorld implements World {
 
     @Override
     public int getMinY() {
-        return 0;
+        return WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMinY();
     }
 
     @Override
     public int getMaxY() {
-        return 255;
+        return WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getVersionMaxY();
     }
 
     @Override