Sonic x Shadow Generations appears to be teasing another secret character

The Japanese website for Sonic x Shadow Generations appears to be teasing another possible playable character.

The Sonic Generations remaster includes both classic and modern Sonic characters, as per the original release, as well as a brand new campaign for nemesis Shadow the Hedgehog.

Under the character section of the website all three characters are shown, along with a blank box with the words "coming soon". But who could it be?

Sonic X Shadow Generations - Summer Game Fest Trailer | PS5 & PS4 Games

Perhaps the most obvious suggestion would be some form of Classic Shadow character to match Sonic. However, Sonic Team's Takashi Iizuka previously told Eurogamer the game would not include Classic Shadow levels, though it will feature 2D elements in the level design.

Presuming this is a playable character to fit in existing levels, could Super Shadow be included as a separate character? Or could we see Metal Sonic as an additional, playable nemesis? (He's already a boss in Sonic's campaign)

Maybe it's not a bad guy at all, which would open the door to anyone: Tails, Knuckles, Amy, Rouge, or even Trip from Sonic Superstars. Dare I say it: Big the Cat fishing minigame?

However, as fan account Tails' Channel suggests, this may not be a playable character at all and just a featured character. In short, don't get your hopes up just yet.

Sonic x Shadow Generations will release on 25th October across PS5, Xbox One/Series X/S, Switch, and PC. That's ahead of the Sonic the Hedgehog 3 film, which will feature Shadow the Hedgehog.