Section started by Andreas Koch.

a) The following games support 4 joystick head-to-head play:
   (Only possible on the 400/800 since only these computer models have
    4 controller ports)

- Ali Baba and the Forty Thieves by Quality Software
- Aliens a PD-game by ??? using an altered Dandy program
  (the Dandy font and thus the graphics were changed, however,
   the levels remain the same and can be used in both games);
- Asteroids cart. by Atari,
- Basketball cart. by Atari,
- Battle Room (CIA vs. KGB) a PD game by SNACC
- Dandy disk by APX,
- Depth Warrior by ??? from ROM magazine, Aug. 1984 ***
- Floyd of the Jungle
- Major League Soccer cart. by Thorn EMI,
- Major League Hockey cart. by Thorn EMI,
- Soccer by Gamma Software
- Hockey by Gamma Software
- Maze War disk or cart. by ???,
- M.U.L.E. disk by Electronic Arts,
- Roadblock by Brian Holness from Compute! magazine
- Silicon Warrior disk or tape by Epyx,
- Sky Warrior by ??? from ROM magazine, June 1984 ***
- Survivor disk or cart. by Synapse,
- Tank Battle by Fred Pinho from Antic magazine:
  http://www.atarimagazines.com/v3n2/animate.html
- Volleyball by ??? (PD game written in Atari BASIC);
- Yellow-Brick-Road by ??? from ROM magazine, Feb. 1984 ***

*** these programs are reported to be 4-player programs, I'm
    not sure if they are meant to be 4-players simultaneously
    or 4-players - one after another (try to find out!);

b) The following games support 4 paddle head-to-head play:

- Castle Crisis by Bryan Edewaard, 2004
- IQ by David S. Maynard for CRL, 1987 (same game as "Worms?")
- Warlords by ?, year? (pd version, unlicensed)
- Worms? by David S. Maynard for Electronic Arts, 1983

c) The following game supports 4 players on all machines, using special
4-button keypad controllers linked together with RJ-11 jacks (standard
phone jacks) to a box with 2 joystick port connectors:

- PQ: The Party Quiz Game by Suncom

d) The following programs support multi-joystick games, using extra
   hardware called Quadrotron (from the German Atari Magazin 2/1989): 
  
- test program for 4 joysticks (and assembler source);
- Quadro-Tron by H.Schoenfeld (4-player Tron-clone);

e) The following programs support multi-joystick games, using extra
   hardware called Multijoy (multijoy4 for up to 4 players, multijoy8 
   for up to 8 players and multijoy16 for up to 16 players; originally
   developed by Raster/Radek Sterba, but also available from ABBUC):

- Astro4Road by Fandal
- Bremspunkt (demo-version) by T. Butschke
- Bremspunkt (full-version) by T. Butschke
- Card Grabber by F. Dingler
- Cervi by R.Sterba
- Cervi 2 by R. Sterba
- Fujirun by Schmutzpuppe (see below!)
- Hardwaretester/Peripheral Test 2.0 by Florian Dingler, 2008
- Icehockey by F. Dingler
- Multijoy-tester by Fandal or Raster
- Multris by R.Sterba
- Quadrotron-M4 by R. Sterba
- Sheep-Race by F.Dingler
- Shot'em All by R.Sterba

The following patches are available at:
http://mitglied.lycos.de/gunnarbusse/bajamar/download.htm
- Asteroids, modified for Multijoy by Schmutzpuppe
- Basketball, modified for Multijoy by Schmutzpuppe
- Tennis, modified for Multijoy by Schmutzpuppe
- Dandy, modified for Multijoy by Schmutzpuppe
- M.U.L.E., modified for Multijoy by Schmutzpuppe

And the following patches are available at:
www.atari.fandal.cz
- Wingman modified for Multijoy by Fandal
- (Thorn EMI) Hockey modified for Multijoy by Fandal
- (Thorn EMI) Soccer modified for Multijoy by Fandal
- (Gamma) Hockey modified for Multijoy by Fandal
- (Gamma) Soccer modified for Multijoy by Fandal
- Battle Room modified for Multijoy by Fandal
- Silicon Warrior by Epyx modified for Multijoy by Fandal
- Mazewar modified for Multijoy by Fandal
- Survivor modified for Multijoy by Fandal
- Floyd of the Jungle modified for Multijoy by Fandal