Quake

Cheat mode:
Press ~ to display the console prompt.
Enter one of the following codes to activate the corresponding cheat function.

Code            Effect
impulse 9       All weapons, unlimited ammo
impulse 11      All weapons, full ammo, all keys
impulse 255     Super shield
god             Invincibility
fly             Press [Space] to fly
noclip          Toggle no clipping mode
give s number   Gain # shells
give h number   Gain # health
give n number   Gain # nails
give r number   Gain # rockets
give c number   Gain # cells
give number     Get weapon #
kill            Commit suicide
notarget        Monsters will not attack unless hit
skill 0 - 3     Sets difficulty level
impulse 13      Silver key
impulse 14      Gold key
Impulse 255     Quadruple damage