Cheat Codes

Despite what iD said in the Quake manual, you can cheat in Quake. At the moment the cheats are:

GOD - makes you invincible (although your armour gets depleted)
NOTARGET - makes monster oblivious to you unless you shoot at them.
FLY - lets you fly through the levels
NOCLIP - Same as DOOM. Lets you walk through walls. Good for finding secrets. Use the [D] and [C] keys to move up and down.
IMPULSE 9 - All weapons & full ammo ( using keys 1 to 8).
IMPULSE 255 - Quad Damage upgrade (doesn't work in Full version)
IMPULSE 11 - Typing several times, gives all Sigils (runestones)
GIVE # - Give weapon #
GIVE H # - Give # of health
GIVE S # - Give # of shells
GIVE R # - Give # of rockets
GIVE C # - Give # of cells
GIVE N # - Give # of nails

You type all of the above cheats directly into the console [~], but better to use the 'bind' command, e.g

bind n "give n 255"
bind 9 "impulse 9"
bind h "give h 255"

This would bind the keys N, H and 9 so by just pressing them, u will get 255 (max. avail.) nails, health, or Full weapons - do the same for the other cheat codes too!!