To Make Ninga Squirrel Fly
To make the Ninga Squirrel fly while you are choosing the Ninga push the following keys: 133568872854. Then dont make your character move for at least a couple of seconds (5). Jump then use the upper cut and use the normal direction buttons and Ninga will fly around.
- Thanks to Paige

All characters and levels:
Enter 8863289202 as a registration code.

Fight as Military Muskrat in two player mode:
Successfully complete the game in single player tournament mode. Select two player mode to have player two have Military Muskrat. Note: This may only be done in the registered version of the game.