Cubot implements Attackable (untested)

Server/src/main/java/net/simon987/server/game/GameObject.java

@@ -257,6 +257,9 @@ public abstract class GameObject implements JSONSerialisable, MongoSerialisable
 
     /**
      * Called before this GameObject is removed from the world - defaults to doing nothing
+     * @return true if cancelled
      */
-    public void onDeadCallback() { }
+    public boolean onDeadCallback() {
+        return false;
+    }
 }

Server/src/main/java/net/simon987/server/game/World.java

@@ -147,9 +147,12 @@ public class World implements MongoSerialisable {
         for (GameObject object : gameObjects.values()) {
             //Clean up dead objects
             if (object.isDead()) {
-                object.onDeadCallback();
-                removeObject(object);
-                //LogManager.LOGGER.fine("Removed object " + object + " id: " + object.getObjectId());
+
+                if (!object.onDeadCallback()) {
+                    removeObject(object);
+                    //LogManager.LOGGER.fine("Removed object " + object + " id: " + object.getObjectId());
+                }
+
             } else if (object instanceof Updatable) {
                 ((Updatable) object).update();
             }