23. Behind the Mask ('The Empire Strikes Back')
While studying under Jedi master Yoda (voiced by Frank Oz) on the eerie swamp planet of Dagobah, Luke is sent into a festering, evil-looking cave. While he's in there, the young man has a vision in which he confronts Vader, decapitates him and watches the weezing Sith Lord's mask break away to reveal...his own face. Welcome to a sobering and chilling foreshadowing of events to come, one which doubles nicely as Luke’s first real failure as a Jedi in training.