Out of the current six Star Wars films, Darth Vader is only a villain about half the time, so long as you don't count being a whiny sociopath in Attack of the Clones as part of this villainy, which maybe you should. If you were to tell that to someone who just walked out of The Empire Strikes Back in 1980 they'd think you were crazy. At one time, Vader was the baddest of the bad. But the moment he killed Emperor Palpatine in Return of the Jedi, Vader become one of cinema's coolest good guys as well. Then the prequel trilogy happened and no one used Vader and "cool" in the same sentence ever again.