When Rey reveals her lightsaber at the end of Star Wars: The Rise of Skywalker, she might have unknowingly revealed the most unstable lightsaber to ever appear in the Star Wars saga. Many Jedi construct their own lightsabers as part of their training. Luke Skywalker memorably built his own green lightsaber after losing his father's lightsaber during the conclusion of The Empire Strikes Back.

Rey builds her lightsaber from fragments of her quarterstaff and junk she finds, adding a turnstile knob to ignite the saber rather than the usual switch. Could this small design choice potentially make Rey rue the day?

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Multiple Kyber Crystals in One Lightsaber

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When Rey ignites her lightsaber, flickers of both blue and green emerge along the blade emitter just before the yellow blade springs forth. Rey has also just buried Leia and Luke's lightsabers in Tatooine, outside Luke's old home. While it is true those blades both shone blue, it may be reasonable to assume Rey somehow found access to Luke's second lightsaber, or at least its kyber crystal, which of course gave off a green hue.

If we can assume that much, it's possible Rey took the kyber crystals from each of those lightsabers and inserted them into her new one to power the device. Again, this is just a theory, but it would make sense, given her reverence for the Skywalker family line, particularly Luke and Leia. Although Rey isn't the only one to have a yellow lightsaber, this color is extremely rare in the main Star Wars movies, really only appearing as an action figure gaffe. Double-sided lightsabers called pikes, which are wielded by the Jedi Temple Guards, also generate yellow light, but were not shown in the movie trilogies.

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Is Rey's Lightsaber Unstable?

While it might be easy to just say, "Rey's lightsaber is made from junk she found, so of course it will be unstable," it's vital to remember that there are several unique, stable lightsaber designs in Star Wars. Rey's emitter reveals the colors of her kyber crystals, but exposed kyber crystals, while uncommon, are not unheard of. Lord Dorwin Corvax's Lightsword from Vader Immortal contains an exposed kyber crystal in its hilt, but the blade remains quite stable.

Even unstable kyber crystals can create functional lightsabers. Kylo Ren's crossguard lightsaber incorporated a cracked kyber crystal, which explains its unstable plasma blade. However, the lightsaber itself never overloaded or blew up in Kylo Ren's hand. Again, it's reasonably to assume, given her talents with machines, that Rey built a suitable and stable lightsaber, even with reclaimed materials and, presumably, with no one there to teach her. The real worry is something rather more simple: the switch to activate the lightsaber is a turning knob.

The mechanism behind this turning knob is less clear. It could offer the lightsaber some sort of adjustability, though it's unclear what, if anything, that would achieve. However, if this turning knob becomes unstable or loose, it might be difficult to deactivate the lightsaber, or too easy to activate on her belt. Of course, many lightsabers have just as many on/off functions; and again, given her acumen with building things and her mastery of the force, Rey will be fine with her bespoke design.

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