diff --git a/core/src/main/java/com/boydti/fawe/FaweAPI.java b/core/src/main/java/com/boydti/fawe/FaweAPI.java
index f4492389..e77547d2 100644
--- a/core/src/main/java/com/boydti/fawe/FaweAPI.java
+++ b/core/src/main/java/com/boydti/fawe/FaweAPI.java
@@ -11,14 +11,13 @@ import com.boydti.fawe.object.PseudoRandom;
 import com.boydti.fawe.object.RegionWrapper;
 import com.boydti.fawe.object.RunnableVal;
 import com.boydti.fawe.object.changeset.DiskStorageHistory;
-import com.boydti.fawe.object.io.FastByteArrayOutputStream;
+import com.boydti.fawe.object.mask.CustomMask;
 import com.boydti.fawe.object.schematic.Schematic;
 import com.boydti.fawe.regions.FaweMaskManager;
 import com.boydti.fawe.util.EditSessionBuilder;
 import com.boydti.fawe.util.MainUtil;
 import com.boydti.fawe.util.MemUtil;
 import com.boydti.fawe.util.SetQueue;
-import com.boydti.fawe.util.StringMan;
 import com.boydti.fawe.util.TaskManager;
 import com.boydti.fawe.util.WEManager;
 import com.boydti.fawe.wrappers.WorldWrapper;
@@ -31,10 +30,13 @@ import com.sk89q.worldedit.EditSession;
 import com.sk89q.worldedit.Vector;
 import com.sk89q.worldedit.WorldEdit;
 import com.sk89q.worldedit.WorldEditException;
+import com.sk89q.worldedit.extension.factory.DefaultMaskParser;
 import com.sk89q.worldedit.extent.Extent;
 import com.sk89q.worldedit.extent.clipboard.Clipboard;
 import com.sk89q.worldedit.extent.clipboard.io.ClipboardFormat;
 import com.sk89q.worldedit.extent.clipboard.io.ClipboardWriter;
+import com.sk89q.worldedit.internal.registry.AbstractFactory;
+import com.sk89q.worldedit.internal.registry.InputParser;
 import com.sk89q.worldedit.regions.Region;
 import com.sk89q.worldedit.world.AbstractWorld;
 import com.sk89q.worldedit.world.World;
@@ -43,10 +45,10 @@ import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
+import java.lang.reflect.Field;
 import java.net.URL;
 import java.nio.channels.Channels;
 import java.nio.channels.ReadableByteChannel;
-import java.nio.file.Files;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -87,6 +89,28 @@ public class FaweAPI {
         return TaskManager.IMP;
     }
 
+    /**
+     * Add a custom mask for use in //mask [values...]
+     * @param mask
+     * @return true if the mask was registered
+     */
+    public static boolean registerMask(CustomMask mask) {
+        try {
+            Field field = AbstractFactory.class.getDeclaredField("parsers");
+            field.setAccessible(true);
+            List<InputParser> parsers = (List<InputParser>) field.get(WorldEdit.getInstance().getMaskFactory());
+            for (InputParser parser : parsers) {
+                if (parser instanceof DefaultMaskParser) {
+                    ((DefaultMaskParser) parser).addMask(mask);
+                    return true;
+                }
+            }
+        } catch (Throwable e) {
+            throw new RuntimeException(e);
+        }
+        return false;
+    }
+
     /**
      * Wrap some object into a FawePlayer<br>
      *     - org.bukkit.entity.Player
diff --git a/core/src/main/java/com/boydti/fawe/object/mask/CustomMask.java b/core/src/main/java/com/boydti/fawe/object/mask/CustomMask.java
new file mode 100644
index 00000000..ad2b2580
--- /dev/null
+++ b/core/src/main/java/com/boydti/fawe/object/mask/CustomMask.java
@@ -0,0 +1,19 @@
+package com.boydti.fawe.object.mask;
+
+import com.sk89q.worldedit.extension.input.ParserContext;
+import com.sk89q.worldedit.function.mask.Mask;
+import java.util.List;
+
+public abstract class CustomMask implements Mask {
+    public CustomMask(List<Mask> masks, String component, ParserContext context) {
+        try {
+            this.getClass(). getConstructor ( List.class, String.class, ParserContext.class ) ;
+        } catch (NoSuchMethodException e) {
+            throw new IllegalArgumentException("Constructor for " + getClass() + " must be <init>(List.class, String.class, ParserContext.class)");
+        }
+    }
+
+    public abstract String description();
+
+    public abstract boolean accepts(String input);
+}
diff --git a/core/src/main/java/com/sk89q/worldedit/extension/factory/DefaultMaskParser.java b/core/src/main/java/com/sk89q/worldedit/extension/factory/DefaultMaskParser.java
index a316515b..d56ce180 100644
--- a/core/src/main/java/com/sk89q/worldedit/extension/factory/DefaultMaskParser.java
+++ b/core/src/main/java/com/sk89q/worldedit/extension/factory/DefaultMaskParser.java
@@ -1,6 +1,7 @@
 package com.sk89q.worldedit.extension.factory;
 
 import com.boydti.fawe.object.mask.AngleMask;
+import com.boydti.fawe.object.mask.CustomMask;
 import com.boydti.fawe.object.mask.DataMask;
 import com.boydti.fawe.object.mask.IdDataMask;
 import com.boydti.fawe.object.mask.IdMask;
@@ -35,11 +36,15 @@ import com.sk89q.worldedit.session.request.RequestSelection;
 import com.sk89q.worldedit.world.biome.BaseBiome;
 import com.sk89q.worldedit.world.biome.Biomes;
 import com.sk89q.worldedit.world.registry.BiomeRegistry;
+import java.lang.reflect.Constructor;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
 
+import static com.google.common.base.Preconditions.checkNotNull;
+
 /**
  * Parses mask input strings.
  */
@@ -49,6 +54,19 @@ public class DefaultMaskParser extends InputParser<Mask> {
         super(worldEdit);
     }
 
+    private static CustomMask[] customMasks;
+
+    public void addMask(CustomMask mask) {
+        checkNotNull(mask);
+        List<CustomMask> list = new ArrayList<>(Arrays.asList(customMasks));
+        list.add(mask);
+        customMasks = list.toArray(new CustomMask[list.size()]);
+    }
+
+    public List<CustomMask> getCustomMasks() {
+        return Arrays.asList(customMasks);
+    }
+
     @Override
     public Mask parseFromInput(String input, ParserContext context) throws InputParseException {
         List<Mask> masks = new ArrayList<Mask>();
@@ -174,6 +192,17 @@ public class DefaultMaskParser extends InputParser<Mask> {
                 }
 
             default:
+                for (CustomMask mask : customMasks) {
+                    if (mask.accepts(component)) {
+                        try {
+                            Constructor<? extends CustomMask> constructor = mask.getClass().getDeclaredConstructor(List.class, String.class, ParserContext.class);
+                            return constructor.newInstance(masks, component, context);
+                        } catch (Throwable e) {
+                            e.printStackTrace();
+                        }
+                    }
+                }
+
                 ParserContext tempContext = new ParserContext(context);
                 tempContext.setRestricted(false);
                 tempContext.setPreferringWildcard(true);