All cheats have to be entered at the main menu!

Invincibility:         L, R, L, R, L, R, L, R
Unlimited ammunition:  WHITE, WHITE, WHITE, WHITE, L, R
Level select:          X, Y, WHITE, WHITE, X, Y, WHITE, WHITE
Flame on:              X, Y, B, X, Y, B
Unlimited Hero Time:   B, X, Y, WHITE, R, L
Liquid metal textures: B, Y, X, B, Y, X
Big heads:             R, R, L, R
Small heads:           L, L, R, L
Pin heads:             L, L, R, L
Exploding fists:       B, X, R, R
Hot fists:             X, B, Y, L, L
Exploding bullets:     L, R, WHITE, Y, B
I Got The Power mode:  WHITE, B, WHITE, B, WHITE, B
Hero mode:             L + Y with a full special meter.