Star Wars: The Clone Wars - Season 4 Episode 21 -

"Brothers" With a magical amulet from Mother Talzin, Savage Opress lands on a junk planet in the Outer Rim, and searches for his lost brother. With the help of the snake-like Morley, Savage finds his brother, discovering that it is no less than the Sith Lord Darth Maul, who has been driven to insanity from his bisection and near-death experience.