Full health and ammunition:

Pause the game and press L1(2), L2(2), L1, R1, L1, R1, R2, R1. Note: Each time this code is used your level will go down by one.

Versus mode:
At the title screen, press Circle, X, Right, Left, Right, Left, Down(2), Up(2). Alternatively, successfully complete the game on any difficulty to unlock Versus mode with five frames and most stages. Successfully complete the game on any difficulty twice to unlock the remaining two frames and stages.

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