Cheat Codes
     Type  [TAB] to open console, type one of the following cheats and
confirm with [ENTER]:

Code:                   Result: 
health                  Full Health 
invisible 1             Invisibility 
ammo                    Full Ammo 
fly                     Fly Mode 
ghost                   Walk Through Walls 
walk                    Normal Mode
playersonly             Freeze Enemies
killpawns               Kill All Enemies