Half-Life
Invincibility:
Press Left, Square, Up, Triangle, Right, Circle,
Down, X at the cheat screen.
Unlimited ammunition:
Press Down, X, Left, Circle, Down, X, Left,
Circle at the cheat screen.
Slow motion mode:
Press Right, Square, Up, Triangle, Right,
Square, Up, Triangle at the cheat screen.
Invisibility:
Press Left, Square, Right, Circle, Left,
Square, Right, Circle at the cheat screen.
Alien mode:
Press Up, Triangle, Up, Triangle, Up,
Triangle, Up, Triangle at the cheat screen.
Xen gravity:
Press Up, Triangle, Down, X, Up, Triangle,
Down, X at the cheat screen.
Bonus levels:
Press Triangle, Square, Left, Right, Circle,
X, Up, Down at the cheat screen. Choose the
"Extras" at the options screen to load new
levels found from other discs, such as the
Official US PlayStation Magazine Issue 57
(June 2002) demo disc.
To get a bonus level in Decay, get one A in
every section. The final level will then become available.
