Fish Revenge is a graphical hack of the game -- it plays exactly the same as the original version -- just having changed game sprites, as the invaders and the Command Alien Ship were made into fish, the player's laser cannon is made into a gun, and the barriers were made into "road blocks" with the initials of "GZ" on top. The background also changes color to yellow with every shot fired by the player and all the fish will start flashing once the flying fish (the Command Alien Ship) appears. The hack was created by Greg Zumwalt.