Jujutsu Kaisen had a rather disappointing conclusion for a wide variety of reasons and Kenjaku, one of its main villains, is usually in the eye of the storm when it comes to those criticisms. The character wasn't truly explored and expanded, leaving several mysteries and questions unanswered, but perhaps the biggest criticism he receives is his plot convenience.
Kenjaku was depicted as a master planner throughout most of Jujutsu Kaisen but there were several instances where the story had moments that were too convenient for him to succeed. Some of these include Suguru Geto and Mahito's appearances, to name two cases. The story wouldn't have happened without these conveniences, making Kenjaku's actions feel more underwhelming.
Disclaimer: This article contains spoilers for the series. Any opinion expressed here belongs to the author and not Sportskeeda as a publication.
Explaining why Kenjaku was extremely lucky during the events of Jujutsu Kaisen
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After centuries of planning the merger and its execution, Kenjaku's vision came to fruition through a series of events that can only be described as lucky. This started with the fact that Toji Fushiguro was born in the Zen'in clan with a Heavenly Restriction and lived a life that eventually led to the murder of Riko Amanai, Tengen's Star Plasma Vessel. This would lead to the radicalization of Suguru Geto, which would prove to be key for the villain.
The fact that Toji became the infamous "Sorcerer Killer" and Geto had the right Cursed Technique were two lucky events, complemented by the Disaster Curses being born all at the same time with Mahito. When it comes to Mahito, the fact he and Geto happened to exist during the same era was another element that benefitted Kenjaku greatly.
Furthermore, Yuji Itadori, a perfect vessel he created for Ryomen Sukuna as a backup plan, accidentally ate the King of Curses' finger and the latter awakened after so many centuries. This was coupled with the fact that Yuji's classmate in Jujutsu High was a Ten Shadows user, Megumi Fushiguro, who would end up becoming Sukuna's new vessel. That gave Kenjaku a chance to deal with Satoru Gojo after the latter was released from the Shadow Realm.
More regarding Kenjaku's luck
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The issue with Kenjaku in Jujutsu Kaisen is that most of his plans were the result of several events taking place at a specific moment in time and everything working in his favor, coupled with the fact that the plot wouldn't have progressed otherwise. It is quite clear that author Gege Akutami didn't have a clear vision for how to advance the story and all of these plot conveniences ended up taking place.
Moreover, while his defeat in the final arc at the ends of Takaba and Yuta Okkotsu would also be quite disappointing, the only reason Kenjaku reached that instance was out of another major plot convenience. During the events of the Culling Games arc, he was about to die at the hands of Yuki Tsukumo's "Bom Ba Ye" ability, but it is revealed that his former body, Kaori Itadori, had the necessary Cursed Technique to deal with this, souring this battle.
Final thoughts
Kenjaku was a villain who had generated a lot of expectations in Jujutsu Kaisen but failed to deliver when it mattered the most. Moreover, the fact that the bulk of his plan consists of sheer luck makes his journey in the story all the more disappointing.
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