Somewhere at Sonic Team is a whole "roadmap of Sonic titles," says head honcho Takashi Iizuka, and the devs "think about which game to release in which year"

Sonic Team head Takashi Iizuka has explained how the studio plans out the releases of Sonic games on a roadmap internally.
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Sonic gets an official lore timeline that goes "tens of thousands of years" into the past and 200 years into the future, and somehow canonizes a party game spin-off

Sonic the Hedgehog will be 34 years old this year, and just in case you wanted to brush up on the complex lore of the series, Sega has released a complete official timeline, stretching from "tens of ...
Polygon

Play as your Sonic the Hedgehog OC with these fan made tabletop games

In the days since Sonic the Hedgehog 3 was released, I’ve been doing a diligent search for the best Sonic-inspired tabletop games out there. And folks, I’ve found them. Surprisingly, there is no ...