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http://www.3dgamers.com/3daction/00archives/quake/cheats.txt.html

              [3D Action Gamers' Archive]  Quake - Cheat codes

Notes on Cheat Code usage:

   * During gameplay hit the tilde (~) key to activate the console
   * Type in the cheat code and press ENTER
   * Hit tilde (~) again to get back to the game with the cheat enabled
   * A couple cheats work as on/off toggles - to deactivate them, simply
     repeat the above steps again

       Code : Description
       ====   ===========
        god : invulnerability (toggle)
       kill : restart current mission
        fly : fly mode: D to go up, C to go down (toggle)
   map ExMy : warp to (E)pisode x, (M)ap y (x,y are numbers)
    skill x : change the skill level (0-3)
   notarget : monsters cannot see you until you attack (toggle)
     noclip : no clipping (toggle)
     give 1 : get axe
     give 2 : get shotgun
     give 3 : get double-barrelled shotgun
     give 4 : get nailgun
     give 5 : get super nailgun
     give 6 : get grenade launcher
     give 7 : get rocket launcher
     give 8 : get thunderbolt
 give s 255 : max shotgun shells
 give n 255 : max nails
 give r 255 : max rockets/grenades
 give c 255 : max thunderbolt cells
 give h 1000: max health
  impulse 9 : get all weapons fully loaded
 impulse 11 : get a rune
 impulse 255: get quad damage

                        Secrets for First 3 Episodes

      ftp://ftp.gamers.org/pub/games/idgames2/docs/rgcq-pips/secrets1
      http://www.gamers.org/pub/games/idgames2/docs/rgcq-pips/secrets1
                 http://www.crl.com/~rhofmann/secrets.html

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                cheats.txt last modified: 04:37 Jan 10 1997
       Copyright c 1996-1997 Piotr Kapiszewski and Frans P. de Vries