It has been almost three years since the Star Wars sequel trilogy concluded, and although Kylo Ren/Ben Solo (Adam Driver) emerged as a pivotal character, the sequels failed to fulfill his potential. From the beginning, Kylo Ren was touted as a morally ambiguous dark side warrior. In Star Wars: The Force Awakens, Ren killed San Tekka with his lightsaber and ordered Phasma to slaughter the whole village, thus making one of the most menacing character introductions ever. Ren also impaled his father, Han Solo, to death at the Starkiller Base.
Rian Johnson's polarizing blockbuster, Star Wars: The Last Jedi, focused on Kylo Ren's vulnerable side and his Force-bond with Rey. Ren destroyed his mask in a fit of rage after being humiliated by Snoke. The movie then ended with Kylo Ren leading the First Order, thus setting up the foundation for him to become the main villain in the subsequent sequel. However, Star Wars: The Rise of Skywalker flattened his character by bringing back Emperor Palpatine. Instead of developing the existing characters, director J.J. Abrams and writer Chris Terrio introduced unwarranted new characters that added almost nothing to the already poorly written story.
Related: Kylo Ren Should've Been Rise of Skywalker's Main Villain (Not Palpatine)
The potential of Kylo Ren as a dark sider felt underutilized in the sequel trilogy. During the development of The Force Awakens, Ren was referred to as «The Jedi Killer» before his name was officially decided. Despite being known as the ''Jedi Killer'' amongst the First Order Rank for preventing the restoration of the Jedi Order, Kylo's ploy to strike Luke Skywalker with his crossguard lightsaber was unsuccessful in their The Last Jedi duel. Hence the Jedi Killer
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