Sonic the Hedgehog 2 is part of a "cinematic universe", according to one of the film's producers.
In production notes alongside the new release, producer Toby Ascher noted the first film was just the start.
"We're creating a Sonic cinematic universe, so we knew we were going to add characters, like Tails and Knuckles; new to the films but beloved by gamers all over the world," he said.
Producer Neal H. Moritz said of the sequel: "[Sonic 1] was a great experience for us as filmmakers, and as movie lovers. Now, we're even more excited to expand that world, adding new characters, bigger worlds, a new, incredible journey, and more action and adventure. There are so many places we can go with Sonic."
As previously reported, a third film in the series has already started production. If Tails and Knuckles are added in this latest film, who could be next? Shadow the Hedgehog? Big the Cat? Rouge the Bat?
A live-action television show is also planned around Knuckles, with Idris Elba reprising the role. It's set to air on Paramount+.
"We've got a remarkable partnership with Paramount," Sega CEO Haruki Satomi previously said "and we are excited to continue expanding the Sonic the Hedgehog franchise with them".
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