Cheat Codes:
Activate the following cheats by pausing the game and pressing the corresponding sequences of buttons:
Invincibility – Hold L and press Up(2), Down(2), Left(2), Right(2), Square, Triangle.
All weapon upgrades – Hold L and press Up(2), Down(2), Left, Right, Left, Right, X, Circle.
Infinite ammo – Hold L and press Triangle(2), X(2), Square, Circle, Square, Circle, Right, Down.
Refill ammo – Hold L and press Triangle(2), X(2), Square, Circle, Square, Circle, Down, Right.