While playing a game, press ~ to display the console window. Then, enter one of 
the following codes to activate the corresponding cheat function:

Result - Cheat Code
Toggle enemy God mode - aigodmode [0 or 1] 
Toggle protectee God mode - aiprotectprotectee [0 or 1] 
Toggle God mode - god [0 or 1] 
Toggle enemy AI cannot hear you - aidisableears [0 or 1] 
Toggle enemy AI cannot see you - aidisableeyes [0 or 1] 
Toggle no clipping - noclip [0 or 1]