Note: This procedure requires editing a game file; creating a backup copy of the file before proceeding is recommended. With a text editor, edit the "config.cfg" file in the game directory. Change the value of the "con_enable" line to "1" to enable the console. Press ~ during game play to display the console. Enter sv_cheats 1 to enable cheat mode. After that, enter one of the following console commands to activate the corresponding cheat function.
CHEAT FUNCTION - CHEAT CODE God mode - god 999 health - health 999 All weapons and ammunition - impulse 101 Ignored by enemies - notarget No clipping mode - noclip