Spellcaster Splinter

Spellcaster Splinter is a parallel universe existence of the Ninja Turtles' sensei. He appears before Leonardo, Michaelangelo, and Donatello after they chase off Gatekeeper Rocksteady and Warrior Bebop, telling them that he is the guardian of four sacred statues. He tasks them with tracking them down to keep them out of the clutches of a Dark Knight, and summons the Warcat for them.

Trivia

 * An action figure of Spellcaster Splinter was intended to release, but never did.