The following article contains major spoilers for Demon Slayer’s final arc.
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TheDemon Slayer: Kimetsu no Yaibaanime is heading towards the final battle. The first movie in theDemon Slayer: Infinity Castle Arctrilogy will begin to adapt the climax of the story, and it will feature some great battles.
As the Demon Slayer Corps storm into Muzan’s lair, they will face the strongest demons out there. The first movie will likely include an emotional battle between Tanjiro and Akaza, and Tanjiro will finally avenge Kyojuro Rengoku. However, the second half of the arc takes an unexpected turn, introducing the most powerful demon ever — and, surprisingly, it’s not Muzan.
The Final Arc Has A Huge Plot Twist
In the Infinity Castle Arc, the Demon Slayers Corps invade the Infinity Castle, which is controlled by Nakime and serves as the true lair of Muzan. With the goal of finding and defeating Muzan, the Demon Slayers split up and storm into the castle. After many great battles and major losses, they finally corner Muzan. Meanwhile,Tanjiro and Tomioka finally kill Akaza, avenging Rengoku, who died early in the series.
AfterNakime is killed in a plot twist, the castle begins to crumble. Muzan then runs away, and the remaining members of the Demon Slayer Corps go after him. Meanwhile, Nezuko waits far away for the antidote to take effect so that she can turn back into her human form. The Demon Slayers have the upper hand in the final battle against Muzan. However, realizing his imminent defeat, Muzan resorts to his final trick — one that brings the most powerful demon ever seen onto the stage.
The Most Powerful Demon Is Not Muzan
Muzan realizes that he is going to be defeated, but he refuses to let his dreams die with him. Desperate,he injects his blood into Tanjiro to turn him into a demon, known as Demon King Tanjiro. While the outside Tanjiro attacks his friends, the inside Tanjiro fights his own battle against Muzan. Muzan tries to convince Tanjiro to give up his mortal form and embrace immortality as a demon.
If you become a demon, you can live forever.
— Muzan Kibutsuji
Nezuko arrives at this point and aids the Demon Slayers in convincing Tanjiro not to give himself up to Muzan. Tanjiro is attacking his former peers while resisting Muzan in his mind. Fortunately, they manage to inject Tanjiro with the antidote before it’s too late.
How Strong Is Demon King Tanjiro?
Apparently, Tanjiro didn’t fully transform into a demon before he was turned back into a human, but we could see a glimpse of his potential. First of all,Demon King Tanjiro was immune to sunlight, giving him a huge advantage compared to the other demons shown in the series. He could also regenerate at an astonishingly fast pace. Furthermore, he was very strong and could apparently assume different forms, just like Muzan.
Had Tanjiro fully become a demon, he would likely have improved his abilities and perhaps acquired new skills. Demon Tanjiro could have achieved Muzan’s dream of immortality if the Demon Slayers Corps hadn’t been quick enough.
Could The Demon Slayer Corps Have Defeated Demon Tanjiro?
Giyu Tomioka states that Tanjiro’s immunity to sunlight means he was probably resistant to theBright Red Nichirin Swords. Resistance does not mean the Nichirin blades wouldn’t work, but they would have a hard time. Considering the strength Demon King Tanjiro displayed during his brief existence, it seemsunlikely that the Demon Slayers could have defeated himhad he fully transformed.
Perhaps the legendary Yoriichi could have defeated him, since Muzan states that Tanjiro was far behind Yoriichi as a Demon Slayer. However, since Yoriichi is long dead, the Demon Slayers were fortunate to be able to quickly inject the antidote and prevent a calamity.
Demon Slayer: Kimetsu no Yaibaisavailable to stream on Crunchyrolland other services. TheDemon Slayer: Infinity Castlemovie will be released in the US and Canada on Jun 08, 2025.
Demon Slayer
Based on Koyoharu Gotouge’s shonen manga, Demon Slayer: Kimetsu no Yaiba is an action anime set in Japan during the early 20th century. Seeking revenge for the murder of his family while also looking to save his sister, Tanjiro joins the Demon Slayer Corps as they try to eradicate Demons led by Muzan.
