Mark Hamill is playing another animated bad guy in an upcoming episode of Teenage Mutant Ninja Turtles.

The Star Wars actor tweeted some concept art of the sinister looking character he'll be playing on the Nick series. "Think there's any chance he's a good guy?" he joked.

The character will be named Kavaxas, Demodragon of the Underworld, and he does not appear to be based on any classic Ninja Turtles protagonists.

Teenage Mutant Ninja Turtles is currently in its fourth season on Nickelodeon. It's the third TV series based on the property, the first beginning in 1987. This rebooted version of the series has done quite well for Nick, and recent episodes have garnered around 1.5 million viewers. The character Hamill plays will be introduced in the Season 5 premiere.

The show is not related to the series of films, the second of which will hit theaters this summer.

In addition to Star Wars, Hamill is known for voice acting work. His most famous voice work is the Joker in Batman: The Animated Series. He will reprise that role for the upcoming Batman: The Killing Joke animated movie, as we previously reported.