Cheat Mode
hold L R Triggers then Down a,x,black,b,a

Unlimited Ammo
L trigger,y,b,up,a,a

Find OSS document
a,b,R trigger,white,black,l trigger

Kill Nemesis
right, left, R trigger, L trigger, x, y

Full Adrenaline
b,y, right,x,a,x

Disable Shell Shock
x, Y , a, b L trigger, x

Turn off HUD
black, L trigger, black, R trigger, UP, Y

Invincibility
Enable the "Cheat mode" code, then press White, Black, Y, White, L(2). Repeat this code to disable its effect. This code must be re-enabled with each new level. Your health will still decrease, but you will not die when it reaches zero. Note: You can still kill yourself with your own bazooka or grenade explosions.

Infinite ammunition
Enable the "Cheat mode" code, then press L, Y, B, Up, A(2). Repeat this code to disable its effect.

Full Adrenaline meter
Enable the "Cheat mode" code, then press B, Y, Right, X, A, X.