Developer Page: D3
(dev id no. 11 - prev next)

D3 Publisher itself. These are all marked as unknown, since I'm not sure whether the company actually develops games - it seems odd that they would have an internal development studio and only use it for four-ish games. So it seems likely that they're actually the work of an uncredited developer. Quite possibly Tose, since they list D3 on this clients page.
Official Site:

Simple 1500 Series
The Puzzle (unconfirmed), The Pro Wres (unconfirmed), The Real Racing: Toyota (unconfirmed)

Simple 2000 Series
The Volleyball (Volleyball Challenge) (unconfirmed)

Simple 2000 Ultimate Series
Gekitou! Meiro King (Maze Action) (unconfirmed), K-1 Premium 2005 Dynamite!! (unconfirmed), K1 World Max 2005 ~Sekai Ouja heno Michi~ (unconfirmed), Sakigake! Otoko Juku (unconfirmed)

Simple Character 2000 Series
Meitantei Conan: The Board Game (unconfirmed), Kidou Butouden G Gundam: The Battle (unconfirmed), Shin Kidou Senki Gundam W: The Battle (unconfirmed), Nantettantei Idol: The Jigsaw Puzzle (unconfirmed)

Simple Wii Series
The Minna de Kart Race (unconfirmed), The Minna de Bass Tsuri Taikai (unconfirmed), The Party Casino (unconfirmed), The Shooting Action (unconfirmed), The Block Kuzushi ~Jisaku Kinou Tsuki~ (unconfirmed), The Wai Wai Combat (unconfirmed)

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