Board Thread:Speculation, Theories, and Rumors/@comment-4892653-20170317204901/@comment-25337730-20170321133524

Ultrasonic9000 wrote: It has been hinted by Shun Nakamura that Sonic was doing something else while Eggman conquered the world. The question is: what could it have been that has kept Sonic out of the loop this much? So... Sonic Chronicles?

I know Sonic Team would probably never reference that game (whether it be because of the legal issues, or the fact not many people played that game), but it's still worth noting.

Also worth noting: Didn't Secret Rings (which is presumed canon thanks to it's reference in Generations) imply that Sonic went on a bunch of adventures inside that book, until he finally made it back to the real world? Just what I heard, I've never finished that abomination of a game. Perhaps in that time period, Eggman could've taken over the planet.