Various cheats
     Enter game code on "game cheats" menu via the Game Options screen

Cheat code:             Effect:
Y B Y Y A X B X         Unlocks all game maps for use in versus modes 
B B A X B Y A B         Unlocks all game costumes and characters 
A B A Y Y X B Y         Auto refill health bars 
B, X, B, Y, A, X, A, A  Unlimited ammo