A new video shared on the Sonic the Hedgehog YouTube channel just made a bunch of things canon, including our crappy recolour OCs. The latest episode of TailsTube even makes it clear that Sonic Boom is canon, at least in the sense that the events of the game took place in a different universe - which of course means Sonic now has a multiverse.
These are far from the only pieces of lore now given a place in the Sonic universe. Sonic Underground, Sonic Riders, and even that old anime movie from the 1990s get shoutouts in the latest TailsTube, giving almost every piece of Sonic media a place in the larger timeline.
The topic comes about when Tails and Amy explain how Classic Sonic came to be, going on to reveal that there are plenty of other Sonics out there too.
As we can see at around the 3:26 mark, a couple of the alternate universe Sonics look very familiar. The first one that'll jump out at you is the 'hog in the middle, who is obviously the blue blur as he appears in Sonic Boom - complete with his blue arms and weird bandage accessories.
The one on the right, however, is a bit more niche. Its purple fur and red eyes strongly suggest that it's inspired by none other than Coldsteel the Hedgehog - a meme OC that's been circulating for years.
The references don't end there either. On Tails' desktop, we can see a file named "Spagonia travel photos", referring to the setting of Sonic Unleashed. Another file mentions "extreme gear", an item introduced in Sonic Riders. Before that, images at the start of the video reference the animated film released in 1999.
All in all, it seems that this short video is part of a larger effort to clamp down on Sonic lore, and start explaining how the universe seems to change with every new game. Sonic Frontiers made many references to other pieces of Sonic media too, including the ongoing comic book series. In November of last year, Sega was even looking to hire a loremaster, so it's safe to assume that there's a reason Tails just casually revealed the existence of the Sonic multiverse.