The codes.
Start the game adding to the command-line -dev -toconsole.
If the orange text doesn't appear, press ~. During gameplay, press ~
and type sv_cheats 1 to enable cheat mode. Now, press ~ and enter any of
the following codes.
/god Invincibility.
/map # Map select. # = map name
/noclip No clipping.
/notarget Opponents ignore character.
/thirdperson Third person view.
impulse 101 All weapons and ammo.
sv_gravity #### Adjust gravity from -999 to 999999.
/give # # = item name to get.
