On the cheats menu, enter the following codes:
Invincibility:
Square, Square, X, Triangle, X, Circle, X, Circle.
Unlock Centepide In "Special Features":
Circle, Circle, Circle, Square, Square, Square, Triangle, Square.
Unlock Missile Command In "Special Features":
Circle, Circle, Circle, Square, Square, Square ,X, X.
50% Less Health for TX in Combat:
X, Triangle, Square, Circle, Triangle, X, Square, Triangle.
50% More Health for TX in Combat:
Square, Triangle, Square, Triangle, Circle, X, Circle, X.
50% More Health in Combat with T800:
Triangle, Triangle, Square, X, Circle, Triangle, Square, Circle.
All FMV:
Triangle, Circle, Square, X, X, X, Triangle, Circle.
All Future Weapons:
X, X, X, Triangle, Circle, Circle, Square, X.
All Past Weapons:
Circle, Circle, Triangle, Square, X, Triangle, Triangle, Square.
All Still Pictures:
X, Square, X, Square, Circle, Triangle, Circle, Triangle.
Centipede Mini-Game:
Circle, Circle, Circle, Square, Square, Square, Triangle, Square.
Complete Mission:
Square, Square, Triangle, Circle, Circle, X, Square, Triangle.
Fight TX Endoskeleton in Every Battle:
Triangle, Square, Triangle, X, Triangle, Triangle, Triangle, Triangle.
Level Select:
Square, Square, Square, Circle, Circle, Circle, Triangle, Triangle.
Missile Command Mini-Game:
Circle, Circle, Circle, Square, Square, X, X.
Quadrupled Damage:
Triangle, Triangle, Triangle, Triangle, Square, X, Circle, Square.
Unlimited Ammo:
X, Triangle, Triangle, Triangle, X, Circle, X, Square.
View Dev Team:
Circle, Circle, Circle, Square, Square, Square, Triangle, X.