Level select
At the code entry screen, press Square(3), Circle(3), Triangle(2). Note: In the PAL version of the game, press Circle(3), Square(3), Triangle(2) at the code entry screen.

Invincibility
At the code entry screen, press Square(2), X, Triangle, X, Circle, X, Circle.

Infinite ammunition
At the code entry screen, press X, Triangle(3), X, Circle, X, Square.

All future weapons
At the code entry screen, press X(3), Triangle, Circle(2), Square, X.

All past weapons
At the code entry screen, press Circle(2), Triangle, Square, X, Triangle(2), Square.

Quadruple damage
At the code entry screen, press Triangle(4), Square, X, Circle, Square.

Mission complete
At the code entry screen, press Square(2), Triangle, Circle(2), X, Square, Triangle.

Fight TX Endoskeleton in all battles
At the code entry screen, press Triangle, Square, Triangle, X, Triangle(4).

50% more health in combat with T800
At the code entry screen, press Triangle(2), Square, X, Circle, Triangle, Square, Circle.

50% more health in combat with TX
At the code entry screen, press Square, Triangle, Square, Triangle, Circle, X, Circle, X.

50% less health in combat with TX
At the code entry screen, press X, Triangle, Square, Circle, Triangle, X, Square, Triangle.

Classic Centipede game
At the code entry screen, press Circle(3), Square(3), Triangle, Square. Alternately, successfully complete the game to unlock the classic Centipede game at the "Atari Games" menu. Note: If it is not unlocked as soon as you complete the game, restart your PlayStation 2, reload your game, and recheck the "Atari Games" menu.

Classic Missile Command game
At the code entry screen, press Circle(3), Square(3), X(2). Alternately, in the vet's office on level 13, walk into the small office on the far right side. Approach the computer and press X to play the classic Missile Command game. Then, successfully complete the level to unlock the game at the "Atari Games" menu.

All FMV sequences
At the code entry screen, press Triangle, Circle, Square, X(3), Triangle, Circle.

All still pictures
At the code entry screen, press X, Square, X, Square, Circle, Triangle, Circle, Triangle.

View development team
At the code entry screen, press Circle(3), Square(3), Triangle, X.

Defeating the Infiltrator
This Boss battle will be your mission in level 5. Press the buttons as instructed by the bottom captions. Do this at random so that the Infiltrator cannot predict your attack. When his health is down by 24, he will get a limp leg which will slow him down.