Unlimited ammunition: Press B, X, B, Y, A, X, A(2) at the title screen. Unlimited health: Press A, B, A, Y(2), X, B, Y at the title screen. Once you or a CPU dies, your/their health bar replenishes to the maximum. All arenas: Press Y, B, Y(2), A, X, B, X at the title screen. All costumes: Press B(2), A, X, B, Y, A, B at the title screen