Sonic Superstars has five playable characters consisting of Sonic, Tails, Knuckles, Amy, and Trip. The first four are available out of the box but Trip the Sungazer has to be unlocked by completing ...
Sonic 3 will continue the tradition of teasing new characters for future films, which could suggest Metal Sonic, Amy, Rouge, ...
Director Jeff Fowler teased that more characters could be revealed in Sonic the Hedgehog 3 for a potential sequel to the trilogy.
The third film in the franchise will continue the tradition after the first two brought Tails and Shadow into the fold.