Rogue One audiences were somewhat surprised at the theater when the movie returned us to planet Mustafar for one scene between Sith Lord Darth Vader and Director Orson Krennic. Vader floats inside his bacta tank, soaking up nutrients while contemplating the Rebels’ demise from the security of his Barad-dûr-like fortress of evil. It’s a fun image, and one that we might see again. But probably minus Vader.

Lucasfilm VP and Executive Creative Director Doug Chiang revealed to Uproxx that the design for the castle was taken straight from original Empire Strikes Back concept art, and we might not have seen the last of it.

It’s interesting, we did a lot of history exploration. Why did Vader build his castle here? Why does it look the way it does? Why does he even come here? For us, it was really figuring out that Vader built his castle on an existing structure, which was this ancient lava dam. And he built it here for a very specific reason. It was to come back here to meditate, to rejuvenate, to reconnect with himself. And it became a very spiritual place, and it was all centered around his bacta tank. And that’s where the form language all built around there. And we’ve done quite a bit of exploration of what’s on the inside of it as well, and hopefully that’ll be seen in some other film.

So that castle is a lot more detailed than the scene or two we saw it in in Rogue One, and it might feature into another Star Wars movie somewhere down the line. A pretty good guess is Kylo Ren’s going to go back there at some point, since he’s obsessed with his grandfather and wants to be as much like him as possible — down to the black outfits and voice-changing helmet. And this just shows how much thought goes into every choice they make for these movies, even if the nuances don’t make it into the final film. There’s a wealth of information to draw from when Lucasfilm starts to expand the universe.

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