Demon Slayer: Infinity Castle trilogy is set to be one of the most iconic anime film series of all time. It is going to adapt some of the most high-stakes battles in the series while also revealing dark secrets that will surprise even the hardcore fans. Ufotable’s animation is known for going over the top with breathtaking visuals, and the trilogy could very well turn out to be its magnum opus.

Although Demon Slayer: Infinity Castle will feature several exciting battles, one in particular will prove to be a decisive clash and have far-reaching consequences. Interestingly, despite being so crucial to the overall premise, Tanjiro and Muzan will not fight in it.

The Fight That Could Seal Muzan’s Fate or End the Demon Slayer Corps

Kokushibo Vs. Muichiro, Gyomei, Sanemi, and Genya

Following the death of Kagaya Ubuyashiki, the Demon Slayer Corps cornered Muzan Kibutsuji, hoping that they would be able to fight him till morning and let the sunlight end his reign of terror. As Gyomei Himejima took advantage of the Demon King’s injuries to unleash a barrage of ruthless attacks, it seemed as though Kagaya’s plan had worked. But in a strange turn of events, Kibutsuji, with the help of Nakime, pushed the Demon Slayer Corps into the Infinity Castle, cornering them instead. This brief battle set the stage for epic clashes in Muzan’s lair that will decide the fate of humanity.

Among the many wars set to be fought in the Infinity Castle, one stands out as the most intense and emotionally charged confrontation. Kokushibo, who has never fought in the past, is set to take on Muichiro Tokito, Genya, Gyomei Himejima, and Sanemi Shinazugawa alone. The Upper Rank One’s life has been shrouded in mystery until now, and fans barely know anything about him. The battle is set to unravel the dark secrets about Kokushibo and his past, which will redefine his identity and lay bare the history behind the Demon Slayer Mark, Breathing Styles, and the Golden Age of Demon Slayers.

But aside from its profound influence on the narrative, Kokushibo’s battle will also be perhaps one of the greatest anime fights of all time. With great swordsmen like Muichiro, Sanemi, and Gyomei fighting their hearts out against one of the most unnerving villains in the series, each moment will feel like a struggle for survival. The raw emotions and Ufotable’s breathtaking choreography are going to leave a lasting impression on the viewers.

Wonderful... The pefect physical form developed to the upmost... How long has it been since I've set my eyes on such a great swordsman? Perhaps 300 years? ~ Kokushibo to Gyomei Himejima

Kokushibo’s battle with Gyomei, Sanemi, Genya, and Muichiro will forever be remembered as the pivotal clash that tipped the scales in favor of either the Demon Slayer Corps or Muzan. As Kibutsuji’s most trusted ally, the Upper Moon One’s victory or defeat will have far-reaching consequences. If Kokushibo comes out on top, the Demon Slayer Corps will lose three of the strongest swordsmen of the current era. This would deal a death blow to the hopes of victory against Muzan. With Kokushibo on his side, Kibutsuji will just become invincible.

On the other hand, if the Upper Moon is defeated, Kibutsuji will lose his most trusted ally and one of the strongest demons to have ever lived. This will dramatically weaken his forces, potentially leaving him to fend for himself. In such a scenario, Kagaya Ubuyashiki’s plan could end up working. That’s why Kokushibo’s fight is so crucial, and the outcome could very much seal the fate of humanity.

Who Has the Upper Hand?

Kokushibo accepted Muzan’s offer to become a demon back in the Sengoku era. Back then, he was a swordsman who had even manifested a Demon Slayer Mark. Even so many years later, he can still use the powers of the mark and is the only demon in existence to have this special ability. The Upper Moon also uses a breathing style along with blood demon art. Furthermore, he has refined his swordmanship for centuries and is able to foresee what most of his rivals can do well before they make their move. This makes Kokushibo a frightening rival with unparalleled strength and combat knowledge.

We are proud to live and die as human beings. Don't act like your worthless ideas are supreme and force them on others. ~ Gyomei to Kokushibo

Luckily, the demon slayers fighting him are also not ordinary. Muichiro Tokito became a demon slayer just two years after picking up a sword. Sanemi and Gyomei are regarded as two of the greatest swordsmen of all time. Meanwhile, Genya’s unique powers give him the extra edge in a battle with any demon. Together, the four combatants could cause serious damage.

Ultimately, the outcome of the battle will depend heavily on its course. If Kokushibo faces these demon slayers one by one, he will have no problem defeating them all without sustaining any serious injury. The only scenario where the Upper Moon can be defeated is if these fighters arrive at the scene almost at the same time. Their unity will be their greatest strength as they face one of the strongest beings in existence. But even in that scenario, their victory won’t come easily and will demand sacrifices that will have far-reaching consequences.

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