Cheats:

 Type the following on the credits screen:

 MEETTHEGUYS     - Start the subgame, winning it supposedly adds
                   extra features
 SENDMEFASTER    - Faster game
 BLOOBABLOOBA    - ???
 NEEDNOBATTERIES - See what the reaper does when there are no live
                   fights..
 YEOLDEGAME      - ???
 TOONSOUND       - Game sound's like cartoon