When starting a new level, pause the game and go to "Settings" then "cheatcodes". Once there, enter the following:
|Up, L, X, L||God Mode|
|Down, Up, Down, Y||All Ammo|
Enter the following codes in the Cheatcodes Menu, in the Settings Menu Option:
|Left, L, X, Left||Gamestop Multiplayer Stage|
|White, Y, X, Black||EB Games Multiplayer Stage|
Thanks to Revolution reader WipeIn!