Tails in Sonic 2 "single player" is a grieving immortal, his soul lashed to the wheel of Sonic's whirling footsteps, doomed to respawn indefinitely until his prickly tormentor finally exhausts their ...

The Transformers X Sonic ... series since Tails' debut in Sonic the Hedgehog 2, and it somewhat resembles the humanoid form that the upgraded version of the plane had in Sonic Adventure 2.