How The Expanded Universe Inspired The Force Awakens
Now that it's been out and we've all had time to digest it, it's starting to become obvious that The Force Awakens took a lot of inspiration from previously existing Star Wars works. After the original movies ended, the franchise continued in a series of novels, comic books, and even video games, creating a rich continuity known as the Expanded Universe. When Disney bought Star Wars, it announced that it wasn't continuing with the Expanded Universe, and that its movies were going to head in a different direction. This was a bummer for fans, but it's clear now that the filmmakers took a lot of inspiration from the E.U. In fact, there are plenty of scenes from The Force Awakens that were clearly inspired by the now defunct Expanded Universe...
Han and Leia's Force-powered kid
During the opening scene of The Force Awakens, we're introduced to Kylo Ren, a Dark Side user who dresses like a toned down Darth Vader. Eventually, it's revealed that Kylo Ren is Han and Leia's son. He was training to become a Jedi at Luke's academy when something happened and he turned to the Dark Side. Now, his parents find themselves on the opposite side from their own child in an intergalactic war. It's also pretty much exactly what happens in the Expanded Universe as well. In those stories, Han and Leia actually have twins: a son named Jacen and a daughter named Jaina. They both grow up to be powerful Jedi, and Jacen is regarded as a hero for a long time. He eventually succumbs to the Dark Side, however, because that's kind of a thing that runs in his family. He starts calling himself Darth Caedus, and his path to becoming a Sith is based on his desire to bring order to the galaxy, no matter what the cost. Both Jacen and Kylo train under Luke Skywalker before turning on their former master. A pattern is starting to become really obvious. If the Skywalkers are the last hope for Jedi in the galaxy, then maybe everyone's better off if without any Jedi at all.
The riot gear Stormtrooper
Typically, Stormtroopers are just nameless grunts. It's even revealed that during the Clone Wars, the troopers are all clones, so they literally have no identities of their own. This trope is challenged twice in The Force Awakens. Finn is introduced early on, and he's one of the first Stormtroopers to show any sort of emotion. When one of his squadmates is killed in front of him, Finn is clearly distraught. He later defects from the New Order, which brands him as a traitor. This introduces the next stand out: the riot gear Stormtrooper. During a battle later on in the film, Finn is recognized by a trooper wearing some beefed up armor and extra weaponry. He calls Finn a traitor and then attacks him, leading to Finn's first lightsaber fight. Surprisingly, the riot trooper's baton is able to withstand blows from a lightsaber, a weapon that previously was able to cut through almost any type of metal. This baton has become one of the stand out additions to Star Wars tech from the film, but it's very similar to a type of lightsaber that already existed in the Expanded Universe. Sure, the original is an actual lightsaber, but it has the same design, and the new weapon is used in a lightsaber duel. The filmmakers changed one minor detail because Stormtroopers can't carry actual lightsabers. That would make lightsabers way less cool if every anonymous Stormtrooper had one.
Luke's exile
The subtitle for Episode VII could have been Luke Skywalker, Where Are You? and it would have been just as accurate. After setting up a new Jedi temple, Luke is betrayed by Kylo Ren and all of his students are killed. At least, that's what's suggested in The Force Awakens. After this happens, Luke goes into a self-imposed exile. It seems like kind of a weird plan, considering that Luke is the only Jedi strong enough to take on Kylo Ren, so leaving kind of puts the galaxy in danger, but hopefully the sequels will fully explain why he left. Once again, events very similar to this happen in the Expanded Universe. When Darth Caedus betrays the Jedi, Luke goes into exile for a period of time. The main difference is that Luke is more active in protecting the galaxy during these stories, as opposed to just standing around on a cliff for a couple of years. Still, the main points are all the same: Luke's student (and nephew) betrays him and Luke goes away for a little while. Sometimes it seems like Jedi look for any excuse to just go live alone on a planet somewhere.
The Starkiller Base
First of all, the Starkiller base is a direct homage to the original Death Star. It's explicitly stated in the movie. The difference is that the Starkiller powers its weapon by draining the energy from a star, and it's able to fire off multiple shots at one time, unlike the Death Star which could only destroy one planet at a time. How lame is that, having to shoot planets one at a time? That just sounds so tedious. One benefit of the Death Star is that it had its own power core, so it didn't have to go sit by a sun and drain it for an hour before it could fire. That aspect of the Starkiller sounds an awful lot like the Sun Crusher. That's a super weapon from the Expanded Universe that uses suns as a weapon, too. The difference there is that instead of draining the energy, the Sun Crusher would fly super close to sun and create a supernova, destroying all the planets in that solar system. The Starkiller seems to be a combination of the Death Star and Sun Crusher. Also, who is in charge of naming these things? Why does everything have to have such a clearly evil name? It's like they want people to rebel.
Benjamin
Even little things, like how characters are named, come from the Expanded Universe. It's revealed early on that Kylo Ren is Han and Leia's son, but it isn't until the end of the movie that his actual name is revealed, Benjamin Solo. This is clearlya reference to old Ben Kenobi, better known as Obi Wan. That's kind of weird, though. His name was Obi Wan, Ben was just a weird nickname that he had while he was in hiding. If Han and Leia wanted to honor Obi Wan, why pick the name he used during the darkest period of his life? It could also be a coincidence, because Leia never really met Obi Wan, she had just heard of him through her adopted father. Luke definitely knew Obi Wan, and in the expanded universe he had a son, and named him Benjamin. Apparently, in the new continuity, Han and Leia are jerks and they stole Luke's meaningful name for their own kid.