Who's in charge of keeping the tally of how many Puyo Puyo's there are now?
Since you tempted me:
1989
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12/??: "Disc Station Special #5 - Christmas" for the MSX2 features a comical dungeon RPG called "Madou Monogatari". (Disc Station was a popular series of MSX disk magazines from Compile.)
1990
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06/15: "Madou Monogatari 1-2-3" for the MSX2. It features the original Madou Monogatari with enhanced graphics, plus a prequel (Madou Monogatari 1) and a sequel (Madou Monogatari 3). This was advertised for several months in the aforementioned Disc Station with dancing Carbuncles.
1991
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??/??: "Disc Station #22" for the MSX2. Arle Nadja and Carbuncle make the title screen (which usually just features generic, highly cute 80's style anime girls which I love to bits). Arle has really big hair here, even for an 80's anime girl.
??/??: "Disc Station #24" for the MSX2 features "Carbunclepi", a spoof of Compile's feline-themed "Nyanpi" puzzle game, new stages of which regularly appeared in Disc Station.
??/??: "Disc Station #25" for the MSX2 features "Wonder Land of Carbuncle", a simplistic shooting game where Carbuncle collects apples falling from a tree while shooting fungi and spiders. He's also on the title screen.
10/25: "Puyo Puyo" for the MSX2. (A sample game can be played on "Disc Station #30".) The Puyos, of course, represent the basic "slime" enemy from the Madou Monogatari games. The original Puyo colors are red, yellow, blue, dark green, light green, and gray.
10/25: "Puyo Puyo" for the Famicom Disk System, published by Tokuma Shoten. It's mostly identical to the MSX version, except you can have the Puyo's replaced with colorful silhouette men.
11/23: "Madou Monogatari 1-2-3" for PC-9801, published by Compile.
1992
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??/??: "Disc Station #32", the final issue of the disk magazine for the MSX (the magazine was continued on Windows PC from this point), features Arle, Carbuncle, Draco, and a blue Puyo on the title screen, along with a bunch of other Compile mascots in the background. (My boy Haagenduck from Madoushi Lulba is squished into the lower left corner!)
10/??: "Puyo Puyo" the arcade version. This is the first one with Sega involvement, as the game was created on Sega C2 hardware and was distributed by Sega. This is also the one that introduces the competition aspect even into the 1-player game, with characters from the Madou Monogatari universe facing off against each other.
12/18: "Puyo Puyo" for Mega Drive, a port of the arcade version published by Sega. This is what became Mean Bean Machine.
1993
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03/19: "Puyo Puyo" for PC-9801, published by Compile. Not sure what version this is based on.
03/19: "Puyo Puyo" for Game Gear, published by Sega. This, again, is what became Mean Bean Machine.
07/23: "Puyo Puyo" for the Famicom, published by Tokuma Shoten. This is the same game as the original disk version, only in cartridge format.
07/23: "Nazo Puyo" for Game Gear, published by Sega. This is based on the puzzle mode from the regular game.
11/??: "Dr. Robotnik's Mean Bean Machine" for Genesis, published by Sega. This is based on the MD port of Sega's arcade Puyo.
12/03: "Madou Monogatari I: Mitsu no Madou Tama" for Game Gear, published by Sega.
12/10: "Super Puyo Puyo" for the Super Famicom, published by Banpresto. This is based on Sega's arcade version, and is what would become Kirby's Avalanche.
12/10: "Nazo Puyo 2" for Game Gear, published by Sega.
12/??: "Dr. Robotnik's Mean Bean Machine" on Game Gear, published by Sega. This is based on the Japanese Game Gear port of the arcade Puyo.
1994
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03/18: "Puyo Puyo" for FM Towns, distributed by CSK. I assume this is a port of the arcade version.
04/22: "Puyo Puyo CD" for PC-Engine CD, published by NEC.
05/20: "Madou Monogatari II: Arle 16sai" for Game Gear, published by Sega.
07/26: "Dr. Robotnik's Mean Bean Machine" on the Master System, published by Tectoy. This is a port of the Game Gear version, and is the only Puyo ever released on Master System (in any country).
07/29: "Puyo Puyo" for X680n0 computer, published by SPS.
07/29: "Nazo Puyo: Arle no Roux (?)" for Game Gear, published by Sega. This hasn't been dumped yet.
07/31: "Puyo Puyo" for Game Boy, published by Banpresto.
10/??: "Puyo Puyo Tsuu" arcade version, once again distributed by Sega. This is still the best game in the entire series.
11/11: "Nazo Puyo" for PC-9801, published by Compile.
12/02: "Puyo Puyo Tsuu" for Mega Drive, published by Sega.
12/16: "Puyo Puyo Tsuu" for Game Gear, published by Compile.
12/30: "Madou Monogatari III: Kyuukyoku Joousama" for Game Gear, published by Sega.
1995
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??/??: "Kirby's Avalanche" for the SNES, published by Nintendo. This is based on "Super Puyo Puyo".
05/26: "Super Nazo Puyo: Rulue no Roux (?)" for the Super Famicom, published by Banpresto. This is sort of an RPG / Puyo puzzle mode hybrid.
05/28: "Puyo Puyo for Windows" for PC-9801, published by Bothtec.
10/27: "Puyo Puyo Tsuu" for PC-9821, published by Compile.
10/27: "Puyo Puyo Tsuu" for Saturn, published by Compile.
11/24: "Madou Monogatari A: Doki-doki Vacation" for Game Gear, published by Compile.
12/08: "Super Puyo Puyo Tsuu" for the Super Famicom, published by Compile.
1996
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01/12: "Madou Monogatari: Hanamaru Daiyouchi Enji" for the Super Famicom, published by Tokuma Shoten.
03/08: "Super Puyo Puyo Tsuu Remix" for the Super Famicom, published by Compile.
03/22: "Madou Monogatari I" for Mega Drive, published by Compile.
03/29: "Puyo Puyo CD Tsuu" for PC-Engine CD, published by NEC.
06/28: "Super Nazo Puyo Tsuu: Rulue no Tetsuwan Hanjouki" for the Super Famicom, published by Compile.
08/02: "Puyo Puyo for Windows95", published by Compile.
11/15: "Puyo Puyo Tsuu" for Windows, published by Compile.
11/15: "Puyo Puyo Tsuu Ketteiban" for PlayStation, published by Compile.
12/13: "Pocket Puyo Puyo Tsuu" for Game Boy, published by Compile.
12/28: "Puyo Puyo for Macintosh", published by Compile.
12/??: "Puyo Puyo Sun" arcade version, running on Sega ST-V hardware. This is Puyo Puyo 3.
1997
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02/14: "Puyo Puyo Sun" for Saturn, published by Compile.
09/04: "Puyo Puyo Sun for SegaNet" on Saturn, published by Compile.
10/30: "Puyo Puyo Sun 64" for N64, published by Compile.
11/27: "Puyo Puyo Sun Ketteiban" for the PlayStation, published by Compile.
1998
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04/02: "Waku-waku Puyo Puyo Dungeon" for Saturn, published by Compile. This is a top-down RPG.
04/17: "Puyo Puyo Sun" for Windows, published by Compile.
07/10: "Compile Gallery 1-2-3" for Windows, featuring Puyo Puyo and Madou Monogatari.
07/23: "Madou Monogatari" for Saturn, published by Compile.
11/27: "Pocket Puyo Puyo Sun" for Game Boy Color, published by Compile.
1999
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03/04: "Puyo Puyo~n" for Dreamcast, published by Sega. This is Puyo Puyo 4, though I don't believe an arcade version was ever released.
03/18: "Waku Puyo Dungeon Ketteiban" for the PlayStation, a port of the Saturn version released by Compile.
08/27: "Puyo Wars" for Game Boy Color, published by Compile. This is a strat RPG that doesn't star any of the Madou cast except for a green Puyo named Puyorin. The protagonist is a cap-wearing, spiky-haired boy hero named Daichi.
??/??: "Puyo Pop" for NeoGeo Pocket Color, published by SNK. This is based on Puyo Tsuu.
12/??: "Puyo Puyo Da!" arcade version, a musical rhythm game distributed by Sega. This runs on Naomi hardware.
12/03: "Puyo Puyo~n Party" for N64, published by Compile.
12/16: "Puyo Puyo~n: Kakkun to Isshou" for the PocketStation, published by Compile. I assume this accompanied an actual PlayStation version of Puyo~n, though I can find no evidence of such a thing...
12/16: "Puyo Puyo Da!" for Dreamcast, published by Sega.
2000
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03/31: "Arle no Bouken: Mahou no Jewel" for Game Boy, published by Compile. This is a Pokemon knock-off starring Arle.
06/16: "Puyo Puyo~n Gashuu" for Windows and Mac, published by Sega. It features Puyo Puyo~n and some extra stuff.
06/16: "Puyo Puyo~n Settei Shiryou Shuu" for Windows and Mac, published by Sega. Just like Gashuu except with even more stuff.
09/22: "Pocket Puyo Puyo~n" for Game Boy Color, published by Compile.
12/21: "Puyo Puyo Box" for PlayStation, published by Compile. I'm not totally sure what's in here, but it seems to include the arcade versions of both Puyo and Tsuu, along with some extra games like Puyo Puyo Quest and Gochamaze Puyo.
2001
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05/25: "Type da Puyo Puyo", a PC typing game published by Biox.
10/18: "Minna de Puyo Puyo" for GBA, published by Sega.
2004
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02/??: "Puyo Puyo Fever" arcade version, distributed by Sega. Though they had partial copyright ownership since 1992 (even the ones released on competing platforms), Sega now has total ownership of the Puyo series following Compile's bankruptcy in 2002.
02/04: "Puyo Puyo Fever" for PlayStation 2, published by Sega.
02/24: "Puyo Puyo Fever" for Dreamcast, published by Sega.
03/24: "Puyo Puyo Fever" for GameCube, published by Sega.
04/24: "Puyo Puyo Fever" for Xbox, published by Sega.
06/24: "Puyo Puyo Fever" for Mac, published by Sega.
07/24: "Puyo Puyo Fever" for GBA, published by Sega.
09/24: "Puyo Puyo Fever" for Windows, published by Sega.
12/24: "Puyo Puyo Fever" for DS, published by Sega.
12/24: "Puyo Puyo Fever" for PSP, published by Sega.
That may not be 100% complete... I have no idea what was released on any of the Disc Stations since they moved to PC (evidently those are pretty rare), and there may be other PC versions that I neglected to mention. Still, in a word:
<img src="
http://ghzforum.nathantsui.com/upload/files/arle.gif"> ばたんきゅー
Oh great more sequels with moderate changes
