Activision Code:
EC8783A81431D934

Alien Mode Cheat:
4CA573BA1456F025

Endless Ammo Cheat:
4CA573721456F025

Invincibility Cheat:
4CA5735A1456F025

Invisibility Cheat:
4CA5738A1456F025

Slow Motion Mode Cheat:
4CA573A21456F025

More Gravity Cheat:
4CA573421456F025