One of the franchise's most powerful but hated villains, Kai Chisaki AKA Overhaul, is the former leader of the villain organization "Shie Hassaikai." His dastardly plan for which he was using the granddaughter of his former leader and creating "quirk destroying bullets" soon came undone by the Pro Heroes and UA interns. The My Hero Academia anime introduced Overhaul in episode 62, while the manga did so in Chapter 115.
While the yakuza and the League of Villains seemed to be getting along, the latter seemingly betrayed the former. The yakuza leader's hideout and the secret behind the bullets were discovered by All Might's former sidekick, Sir Nighteye. The Pro Heroes soon blasted the Shie Hassaikai hideout in an attempt to free Eri, the granddaughter of the former yakuza leader, and apprehend Overhaul.
After Deku defeated Overhaul, the Police escorted the former yakuza leader to the hospital and then prison. However, the trip was cut short after being interrupted by Shigaraki, Dabi, and a few other League of Villains members. Shigaraki seemingly exacted his revenge on Chisaki and took the last remaining "quirk destroying bullets," leaving the latter to die. This scene has had many fans wondering if Overhaul will return as a villain or if he's dead. Read on to find out.
Overhaul's final battle against Izuku ended pretty severely for the yakuza leader. Of course, this was also because Eri used her quirk "rewind," which gives the user the ability to reverse a living being's body back to a previous state, on Deku allowing him to use One For All at 100% of its power.
Following the downfall of the Shie Hassaikai, Kai Chisaki and ten members of the Yakuza organization are transported toward the villain hospital in Takodana via Police escort. Toga and Twice report the development to Mr. Compress and the others, and the League of Villains uses the highway to intercept the convoy in a truck. The Police confiscate the Quirk-Destroying Drugs and the villain's personal belongings.
The villains overpower the police escorts and isolate Overhaul from the rest of the convoy. Shigaraki takes off his mask and tells Overhaul that he hates him because he's arrogant. Mr. Compress uses his quirk to take away Chisaki's left arm. Tomura calls Chisaki a hypocrite, noting the irony in his plans to erase a quirk when he uses a quirk to achieve his goals. He then touches Overhaul's right forearm, which begins to disintegrate.
As the decay begins to spread across his arm, Shigaraki takes out a knife and amputates Overhaul's arm, preventing him from dying. Overhaul is horrified at Tomura's actions and screams in frustration as Shigaraki tells him that all he can do now is envy everybody else's quirks. Shigaraki then maniacally laughs at Overhaul for being "quirkless," the very thing he wanted to turn everyone else into.
The League of Villains then leaves Overhaul after Spinner reminds them that reinforcements are on their way. Seeing these events, we can be sure that Overhaul is indeed alive. Kai Chisaki, AKA Overhaul, is currently imprisoned in Tartarus, serving a life sentence for his crimes. As for his quirk, technically, Chisaki still has his quirk "overhaul." However, usage of his quirk requires his hands, which have now been cut off. So yes, Overhaul is essentially quirkless in the sense that he can never use his quirk again.
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