diff --git a/src/main/java/com/sk89q/worldedit/masks/CombinedMask.java b/src/main/java/com/sk89q/worldedit/masks/CombinedMask.java
index fa618a81d..7ec96fdc6 100644
--- a/src/main/java/com/sk89q/worldedit/masks/CombinedMask.java
+++ b/src/main/java/com/sk89q/worldedit/masks/CombinedMask.java
@@ -38,7 +38,7 @@ public class CombinedMask implements Mask {
     }
 
     public CombinedMask(List<Mask> masks) {
-        masks.addAll(masks);
+        this.masks.addAll(masks);
     }
 
     public void add(Mask mask) {