diff --git a/src/main/java/com/sk89q/worldedit/EditSession.java b/src/main/java/com/sk89q/worldedit/EditSession.java
index c7c2aca03..cc6ce130c 100644
--- a/src/main/java/com/sk89q/worldedit/EditSession.java
+++ b/src/main/java/com/sk89q/worldedit/EditSession.java
@@ -1313,11 +1313,7 @@ public class EditSession implements Extent {
         MaskIntersection mask = new MaskIntersection(
                 new BoundedHeightMask(0, getWorld().getMaxY()),
                 new RegionMask(new EllipsoidRegion(null, origin, new Vector(radius, radius, radius))),
-                new BlockMask(this,
-                        new BaseBlock(BlockID.STATIONARY_LAVA, -1),
-                        new BaseBlock(BlockID.LAVA, -1),
-                        new BaseBlock(BlockID.STATIONARY_WATER, -1),
-                        new BaseBlock(BlockID.WATER, -1)));
+                getWorld().createLiquidMask());
 
         BlockReplace replace = new BlockReplace(this, new BlockPattern(new BaseBlock(BlockID.AIR)));
         RecursiveVisitor visitor = new RecursiveVisitor(mask, replace);
diff --git a/src/main/java/com/sk89q/worldedit/LocalWorld.java b/src/main/java/com/sk89q/worldedit/LocalWorld.java
index e4659459c..b2cf7638d 100644
--- a/src/main/java/com/sk89q/worldedit/LocalWorld.java
+++ b/src/main/java/com/sk89q/worldedit/LocalWorld.java
@@ -23,6 +23,8 @@ import com.sk89q.worldedit.blocks.*;
 import com.sk89q.worldedit.extent.Extent;
 import com.sk89q.worldedit.foundation.Block;
 import com.sk89q.worldedit.foundation.World;
+import com.sk89q.worldedit.function.mask.BlockMask;
+import com.sk89q.worldedit.function.mask.Mask;
 import com.sk89q.worldedit.regions.Region;
 import com.sk89q.worldedit.util.TreeGenerator;
 
@@ -35,6 +37,7 @@ import java.util.Random;
  * @author sk89q
  */
 public abstract class LocalWorld implements World, Extent {
+
     /**
      * Named flags to use as parameters to {@link LocalWorld#killMobs(Vector, double, int)}
      */
@@ -599,4 +602,20 @@ public abstract class LocalWorld implements World, Extent {
             return new BaseBlock(type, data);
         }
     }
+
+    /**
+     * Create a mask that matches all liquids.
+     * </p>
+     * Implementations should override this so that custom liquids are supported.
+     *
+     * @return a mask
+     */
+    public Mask createLiquidMask() {
+        return new BlockMask(this,
+                new BaseBlock(BlockID.STATIONARY_LAVA, -1),
+                new BaseBlock(BlockID.LAVA, -1),
+                new BaseBlock(BlockID.STATIONARY_WATER, -1),
+                new BaseBlock(BlockID.WATER, -1));
+    }
+
 }