AUFUto asks Sonic how does he have so much forms.

Sonic: well the super and hyper form are thanks to the chaos and super emeralds, the Darkspine form from the world rings, and werewolf from Dr. Eggman which I didn't like, and then there's the excalibur me but I didn't think of that as a transformation. Dark Sonic is non-canon though which is sad for all of the fans. Everything else out of what I know is also non-canon.

Lolcram11: there's your answer! Make sure to Ask or Dare and Vote!