This post contains a minor SPOILER for Star Wars: The Rise of Skywalker.

Without revealing too much, Star Wars: The Rise of Skywalker’s opening scene is pretty intense. It features Kylo Ren (Adam Driver), relentlessly slashing through a group of hooded victims as he for a “wayfinder,” a GPS device that will help him locate the Sith planet Exegol. He’s surrounded by an eerie forest swathed in blood red light, a planet that is neither mentioned nor visited again for the rest of the movie. But now, thanks to the canon reference guide Star Wars: The Rise of Skywalker: The Visual Dictionary, that location is revealed. And it turns out it’s actually a location we’ve totally seen before in another Star Wars movie.

The planet on which we first see Kylo Ren is Mustafar, AKA the lava planet where the young Anakin Skywalker turned Darth Vader lost his limbs in a confrontation with Obi Wan Kenobi in Revenge of the Sith. According to the guide, written by Pablo Hidalgo: "Kylo soon outpaces his stormtrooper escorts as he cuts a swath of destruction through the Alazmec who attempt to block his path to Vader’s castle — or rather, its crumbling ruins. Kylo enters the castle grounds with purpose, and finds an ark containing an artifact that will lead him to answers.”

Yes, that’s right. Vader also chooses Mustafar to be the location of his black castle, as seen in Rogue One. The "Alazmec" that Hidalgo refers to are "cult colonists" who travel far and wide to Mustafar in attempts to gain the power that corrupted Darth Vader many moons ago. It makes complete sense that Kylo Ren, who has been seeking to avenge Vader since The Force Awakens, would come here.

“But wait!” you protest. “I don’t remember the lava planet having a forest of trees!” And you would be correct. The guide specifies that these trees are known as “irontrees,” which were planted by the Alazmec “in a futile attempt to reinvigorate the glen that covered the land centuries earlier.”

Star Wars: The Rise of Skywalker is in theaters now.

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