Spoiler Alert: This article contains developments from the Demon Slayer manga series.Demon Slayer: Kimetsu no Yaiba’supcoming “Infinity Castle Arc” movie trilogy hosts the series’ most intense and decisive clashes that will unearth vital moments through breathtaking battle choreography and hard-hitting revelations. Central slayers and demons are at the hub of this narrative, with Kamado Tanjiro and Kibutsuji Muzan on the frontlines as the battle warheads.
So far, inDemon Slayer: Kimetsu no Yaiba’sanime, the demon race’s progenitor, Muzan Kibutsuji, is portrayed as the most powerful demon in the series. While this is true for the majority ofDemon Slayer,Kamado Tanjiro usurps the “strongest” titlefrom the tyrannical leader towards the end of the story.

The truly defining factor that places Tanjiro among the upper echelon of the series’ most formidable fighters is his invulnerability. He becomes the perfect demon, surpassing Muzan in specific ways that override his stake in the demon power ranking hierarchy.
Muzan’s Demise Set The Pathway For The Birth of Demon Slayer’s Strongest Demon
His Last Miserable Attempt at Survival Led to Demon King Tanjiro’s Emergence
Despite the rushed nature of the Infinity Castle Arc, the finale’s grimness makes it one of the most impactful moments in the manga series.Infinity Castle Arc is the culmination of eventsinvolving the Demon Slayer Corps' efforts to reach and eliminate demon-leader Muzan, a plague to humanity that has caused untold suffering for centuries.
Kaguya Ubuyashiki’s sacrificial death catalyses this grim development, leading to heated clashes between the Hashira and battle-worthy members of the corps and Muzan’s progeny. During this intense fray, notable members of the Hashira like Obanai Iguro, Mitsuri Kanroji, and Gyomei Himejima are laid to rest in battle.

The titular protagonist also nearly breached the door of death. For context, the Demon Slayer Corps succeeded in killing Muzan by banking on the villain’s fatal sun weakness. Due to torturous exposure from the Sun, Muzan disintegrates completely, but not before embedding his cells into Tanjiro.
Tanjiro, who had received deathly blows from repeated clashes with Muzan, goes through a life-resetting change that transforms him into a demon that carries the vestiges of Muzan’s ill will against humanity. Essentially, Muzan’s essence fully bonded with the slayer, creating a pseudo-demon king with regenerative abilities comparable to his precursor.
Demon King Tanjiro Doesn’t Have Any Weaknesses Peculiar To Demons
He Surpassed Muzan in Terms of Vulnerability
Debuting in #chapter 201 of theDemon Slayermanga, Tanjiro’s ascension to a demon king is apparent with an instant regeneration of his arm and one-half of his face that was brutally injured in the previous battles.
Moments later, readers discover that the Sun, which is a universal weakness of demons, doesn’t deal any damage to the revived Tanjiro. These sensational twists of events can be referenced to the Kamado bloodline heritage, as fans would remember that Nezuko equally conquered the Sun; it was the decisive trigger that led to the final clash between the corps and Muzan.
This special trait hits with a devastating reality for the now weakened Demon Slayer corps, evidently failing to subjugate Tanjiro, whose amplified physical traits easily overwhelm his former allies. In #chapter 201, Inosuke tries to slice Tanjiro’s head, but his blade bounces off the hardened strength of Tanjiro’s neck.
Tanjiro is the perfect demon; he gains incredible durability without being susceptible to the sun.
These sequences point to the unmistakable conclusion that Demon King Tanjiro is a Hashira-level threat, just like the Upper Moon demons — Muzan’s elite battle force. However, unlike them, Tanjiro is the perfect demon; he gains incredible durability without being susceptible to the sun.
Theoretically, Tanjiro should be stronger than Muzan, considering the fact that even though he hasn’t ingested humans to increase his strength, his characteristics are comparable to Muzan and the Upper Moons. For clearer emphasis, Muzan’s life was foiled by the sun, and Tanjiro surpassed this setback, implying that there is no known weakness of the character.
Tanjiro eventually regains his human consciousness, letting go of his demonic form thanks to the persuasive interventions of his loving comrades, enabling him to break free of Muzan’s hold on his free will. Regardless, that short transformation is enough to brandTanjiro with the “strongest demon” title inDemon Slayer, as his potential to wreak havoc as a demon king would be unfathomable.