[Focused on Sun, Star and Moon version primarily]
[if you have something I'm missing please let me know! ellie at cybergrunge . net send an email! :]

JA Sun version box

JA Star version box

JA Moon version box

Comic Bom Bom Special

Comic Bom Bom box

Release Timeline

 JP  Robot Ponkottsu: Sun & Star Versions, December 4th, 1998.
 JP  Robot Ponkottsu: Moon Version, December 24th, 1999.
 JP  Robot Poncots Comic Bom Bom Special Version 2000 ???
 US  Robopon Sun Version, December 4th, 2000.

Star and Moon never made it outside Japan, making it impossible to "collect them all" as several Robopon could only be acquired through trading. This was a sore spot for me and many others growing up, but I was also endlessly fascinated by the accidental Unobtainium.

Even more versions

In the gigaleaks, it was revealed that there is an extant English language ROM of Star version, DMGHRCE0.2 but for whatever reason actual cartridges were never made. Moon Version is definitively JP-only, which is unfortunate because it has updated, game-exclusive sprites. The Comic Bom Bom Special Version was limited to 500 copies. The ROM is DMGARTJ0.1, and it appears to indeed simply be the Japanese Sun version, but limited to Super Game Boy mode for some reason, not sure what makes it different. In 2019, Deoxyz of Hidden Palace found an early prototype cart on ebay which turned out to be Sun Version, although with tons of typos and minor differences.

Existing 1st-gen ROM's:

Robopon - Star Version (USA) (Proto).gbc
Robopon - Star Version (USA).gb
Robot Ponkottsu - Sun Version (Japan) (Rev 0 Sample).gb
Robopon - Sun Version (USA) (Beta) (SGB Enhanced) (GB Compatible).gbc 
Robopon - Sun Version (USA) (SGB Enhanced) (GB Compatible).gbc 
Robopon - Sun Version (U) [C][!].gbc
Robot Ponkots - Sun Version - Comic Bom Bom Special Version (Japan) (SGB Enhanced).gb
Robot Poncots - Moon Version (Japan) (SGB Enhanced) (GB Compatible).gb

Official media

USA release box cover scan

USA release box back scan

USA Star Version box

Unreleased, unknown source

Robopon Sun Version Game Boy Color Instruction Booklet.pdf

Robopon Vol. 1 Book 1 - these are the only images I've found of the manga, which apparently ran pretty long in Comic Bom Bom. You can see Tamori Hataru's distinctive, comedically grotesque style in the manga. Translations would be awesome but nobody has yet translated them.

Trading Card Game

I've found almost no reference online anywhere to the trading card game, which apparently was only in Japanese. Here are all the images I could find. If you know any more about it please contact me!!!

Action Figures

These are the only images I could find of the official action figures. They seem to be extremely rare, if you know anything more about them or have better pictures contact me!!!

Development and Credits

Some background on who actually made the game is good to have. Robopon was released within the same month as another game by Hudson: the Pokemon Trading Card Game for Game Boy. I got both of them as soon as they came out, and the Pokemon TCG was actually an incredibly fun game, its battle mechanics were even more satisfying than the 1st Gen Pokemon games, it was really addictive. The style of PTCG was really similar in a lot of ways to Robopon.

Depending where you look, you will see development as credited to Will Co., Ltd., to RED Company, and to Atlus and Hudson Soft. All of these folks seemed to work pretty closely. Its a bit hard to find any info on Will Co., Ltd. specifically, other than being listed as a development company for various games of that era.

The Robopon credits is also a who's who of Bomberman and Mario Party folks, as well as a ton of the same programmers who worked on the Tengai Makyō, Sakura Wars, and Sakura Taisen franchises, which in turn shared a ton of producers and programmers with Pokemon Blue and Red version.

Tatsuo Masuda is credited as the game designer, and is Alum of Mario Party, associate producer of the PSP & PS Vita Bomberman games, and helped with the planning of John Romero's Daikatana for Game Boy Color, a very beautiful RPG.

Tadashi Ozaki, Robopon's Game Coordinator was also the director of Bomberman for the Game Boy Advance. Robopon producer Hidetoshi Endō is also listed as Producer or Supervisor to almost every Mario Party and Bomberman game up to as late as 2018. Chief designer Atsushi Shimoda worked on Cosmic Fantasy: Bōken Shōnen Yū for the TurboGrafx CD.

Interestingly the game that shares the bulk of Robopon's production and development staff is the Silent Hill Visual Novel game for Game Boy Advance.