Get full health:
At the start screen enter the following combo... X, X, X, X, Square, Square, Square, Square, Circle, Circle, Circle, Circle
Get unlimited arrows:
At the start screen enter the following combo... X, Circle, Square, Square, X, Square, Circle, Circle, X, Square, Square, X
Get stronger opponents:
At the start screen enter the following combo... X, Circle, Square, Square, X, Square, Circle, Circle, X, Circle, Circle, X
Get weaker opponents:
At the start screen enter the following combo... X, Circle, Circle, Square, X, Square, Square, Circle