When the Mega Drive was finally retired and replaced by the Sega Saturn in late 1994, most people expected a new Sonic platformer to lead the new console into the future. But... nothing of the sort ever came to pass (compare this to a Nintendo console without a Mario adventure to understand just how strange this seemed), even though a high-profile 1992 survey showed that Sonic was more popular among children than both Mario and Mickey Mouse in the U.S.
It wasn't until the Dreamcast in 1998 that Sonic was unleashed in a new adventure, more specifically in Sonic Adventure. But one might suspect that it went through several revisions, and began its journey as a potential Sega Saturn title. Whatever the case may be, the official Sonic account on Bluesky has shared early concept art from Sonic Adventure.
They show a Sonic game that could have looked quite different, including characters that bear more resemblance to Dr. Robotnik's design than the more "normal" people we encountered in the game, as well as an early version of what we assume is Mystic Ruins. It also appears that Sonic himself was initially intended to have a design more closely resembling his appearance during the Mega Drive era.
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