If you're not already familiar with the Star Wars expanded universe don't worry I'm not either. However when the first trailer was released I did do some research into it trying to figure out the identity of the new villain. However after seeing the movie I discovered that while they seem to have drawn some inspiration from the expanded universe a lot was changed.
First off we have Shira Elan Colla Brie AKA Lumiya. Though it doesn't actually refer to her using the title Darth it does say that she was the Sith Lord who turned Han Solo's son to the Dark side. She does have that alias though so I kind of imagine that her name should be Darth Lumiya. Instead what we got was Supreme Leader Snoke. There is no known alias for Snoke, at least not at this time. Unfortunately at this point there is probably no way we can get Snoke changed back to Lumiya. They're just too different to fix that. As long as they stick the Darth title on his name at some point I'm OK with that though as Lumiya didn't use it either and it really should be there.
We've been told about Darth Plagueis, we had Darth Sidious even though he wasn't always called that and didn't even know that name till the prequels were made, Darth Maul, Darth Tyrannus though again that name was so rarely heard in the films that most people didn't even realize it was Count Dooku's Sith name, and of course Darth Vader. I feel like this new movie is trying to ignore the existence of the prequels by abandoning the title used for every Sith Lord. This being said, Kylo Ren was actually suppose to be called Darth Caedus.
Changing the name of Darth Caedus to Kylo Ren wasn't the only name change made to that character. The idea of him being the son of Han and Leia Solo was completely accurate to the expanded universe however his name was Jacen not Ben. Ben is actually the name Luke Skywalker's son and it makes more sense for Luke to name his son after Obi-Wan Kenobi than for Han and Leia. Han never really liked Old Ben Kenobi and Leia never really knew him. She knew about him but the two of them never actually spoke, he was killed during her rescue from the Death Star. Luke is the only one who really had any attachment to him.
Now over all this was still a really great movie but I seriously think they need to do some Audio Dialog Replacement to record new lines for this movie removing every mention of the Knights of Ren, changing Ben back to Jacen, and replacing every mention of Kylo Ren to Darth Caedus. The actor even looks like Jacen Solo so I don't know why they changed his name. Kylo Ren is just a really stupid name. Knowing all this, even if they don't change it back to the way it was, I'm refusing to use his new names. As far as I'm concerned his name is Jacen Solo/Darth Caedus, I don't care what Disney says.
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