The final confrontation between Luke, Darth Vader and the Emperor could have looked even more intense, going by these storyboards from Star Wars: Return of the Jedi. In particular, the Emperor looks sort of like Darth Maul crossed with the Joker, in some of these storyboards by artist David Russell.
These images come from an interview with Russell over at The Movie Blog, in which he talks about being influenced by Jack Kirby, and his friendship with author Jack Vance that got him in the door at Lucasfilm. There are more storyboards, plus a whole slew of storyboards from Tim Burton's Batman, at the link. Check out some more of our favorite images from the Return of the Jedi storyboards in this gallery.