Codes for Quake64
Go to the password screen and type in all Q's, It
will tell you the password is invalid. Then go to the
option screen, you will now see the word debug, go
to debug and you have the ability to select any
maps, god mode, all weapons, and the monsters
will not attack you.
Walk Through Walls
Go to the password screen and type NOCLIP. If you do it right you can walk through walls!