Ray, the Flying Squirrel

Ray the Flying Squirrel is a member of the Chaotix and best friends with Mighty the Armadillo, having met him while both were held prisoner by Dr. Ivo Robotnik. The two teamed up with Sonic the Hedgehog during an escape attempt, but Ray ended up being trapped when he grabbed the prison's Power Stone energy source and was caught in a time warp. Years later, Mighty found and freed him, bringing him back to Angel Island. Joining the Chaotix, Ray became a loyal, if timid, member, helping them face various foes on the island and then later on the surface as they fought Doctor Eggman alongside the Freedom Fighters. Later, Ray also became a part-time resident of New Mobotropolis.

If you look closely, he kind of looks like Tails.