Mark Richard Hamill (born September 25, 1951) is an American actor, voice artist, producer, director, and writer, best known for his role as Luke Skywalker in the original Star Wars trilogy. More recently, he has received acclaim for his voice work, in such roles as the Joker in Batman: The Animated Series and various other animated series, films, and video games.
He is best known on Nickelodeon as Firelord Ozai on Avatar: The Last Airbender. He also voiced the villain Undergrowth in the Danny Phantom episode "Urban Jungle", and the Mermaid Man and Barnacle Boy villain The Moth in the SpongeBob SquarePants episode "Night Light". He also appeared as Pel in the Space Cases episode "A Day in the Life".