Choose Level:
At the main menu, hold Select and quickly press Triangle(3). Then, press Square, X, Square,
Triangle, X, Triangle, Circle, Square. Begin a new game, then hold Select and press Left or Right at
the mission introduction screen to choose a new starting level.

Invincibility:
At the main menu, hold Select and quickly press Triangle(3). Then, press Triangle, Circle(2),
Triangle, Circle, Square, X(2).

Super Gun:
At the main menu, hold Select and quickly press Triangle(3). Then, press X, Circle, Triangle, X(2),
Circle, X, Square.

Invisibility:
At the main menu, hold Select and quickly press Triangle(3). Then, press Square, Triangle, X,
Square, Triangle, Circle, X, Triangle.

Overhead View:
At the main menu, hold Select and quickly press Triangle(3). Then, press Triangle(2), X(2), Square,
Circle, Square, X.