“Stop thinking of the Dark Side as some pathway to power. That’s the Emperor lying to you. It’s destructive. Darth Vader is miserable. He lost everything. He has nothing. He has no one in his life. Absolutely nothing, until his son comes back and says, ‘I love you.’ That’s it. Other than that, his life is a wreck. You get that power, but at what cost? The Emperor has no one, nothing around him but fear and hate. And that’s no way to live your life.”
-Dave Filoni
SPOILER SPOILERS SPOILERS
http://ew.com/tv/2018/03/05/star-wars-rebels-final-episode-finale/2/