Concept art for Star Wars: The Rise of Skywalker of fights between Rey and Kylo Ren reveals even more missed opportunities to turn Rey into the unique Jedi that she could have been. After Star Wars: The Last Jedi proposed the possibility that Rey (Daisy Ridley) descended from no previously established Star Wars characters,The Rise of Skywalker retconned that by officially confirming Rey to be a Palpatine. The first Palpatine hint for Rey in The Rise of Skywalker is her sudden use of Force lightning on a First Order transport ship that she thinks is carrying Chewbacca. While Force lightning is a power not restricted to the Palpatine lineage, for many characters are presented using different color variants of Force lightning in Star Warscanon, it did pose a much stronger possibility of Rey being able to truly balance between the Sith and Jedi worlds as the Jedi Order strongly discourages using Force lightning.
Despite this, Star Wars never fully commits to the idea of Rey being the first Gray Jedi on screen. Rey consistently finds herself wrestling with temptations from the dark side only to commit to the light side in the end. Especially with Luke (Mark Hamill) emphasizing the importance of balance in the Force in The Last Jedi, the sequel trilogy had the opportunity to branch away from a more dichotomous treatment between the light and dark sides of the Force. If Rey were to balance between the Sith and Jedi Orders, the sequels would have presented enticing ways to explore the Force in more depth.
Related: Rise Of Skywalker: Why Rey's Force Lightning Is Different From Palpatine's
As this Dark Rey concept art for The Rise of Skywalker proved, Rey had a lot more potential to be a completely different Jedi in Star Wars.
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