Press ~ to display the console window. Type
hash sv_cheats 1 and press [Enter] to enable cheat
mode. Enter one of the following codes at the console window to
activate the corresponding cheat function. Note: Cheats may have
to be re-activated after starting a new level.

Code
Toggle God mode god
Toggles no clipping mode noclip
All weapons and ammo give all
Spawn indicated item or NPC give
Armor give armor
Full ammunition for current weapons give ammo
Health give health
Stamina give stamina
Unlimited power pinkspider
Disable enemy AI notarget
Never get tired nofatigue
List console commands cmdlist
Display current map name mapname
List maps dir maps
Advance to indicated map map, spdevmap or devmap
Level select icon at main menu raven 1
Change gravity; 800 is default, set to 0 to fly
g_gravity <0-800>
Change movement rate; 320 is defeault, lower is slower
g_speed
Change player's name name
Toggle windowed and full screen; will restart game
toggle r_fullscreen
Show current server settings serverinfo
Reconnect to last server reconnect
Suicide kill
Have dialogue said out loud /sounds or /sounds2
Exit game quit
Trainer