Cheat Codes

IDDQD = GOD MODE
IDKFA = ALL KEYS AND FULL AMMO
IDCLIP = WALK THROUGH WALLS
IDMYPOS = CO-ORDINATES
IDDT = MAP ADD ON
IDCHOPPERS = GIVES YOU A CHAINSAW

for Network cheat:

in map mode, hold down ALT and type IDDT 4 times