Summary
With the conclusion ofthe Hashira Training arc, fans ofDemon Slayercannot wait to see the next season, theInfinity Castle arc. The ending of the Hashira Training arcwas super tense and exciting. The long-awaited battle between the Demon Slayers and Muzan and his upper demons will take place in the Infinity Castle. What began as the journey of a boy trying to save his little sister, who is a demon, has now reached a crucial defining moment of their lives.
For viewers ofDemon Slayer, this beautifully animated series has built up to this battle with a series of key events. A lot of important developments will shape the outcome of the Infinity Castle arc, from Muzan’s regeneration ability to the structure of the Infinity Castle.For those heading intoDemon Slayer’sInfinity Castle arc, these are the things they need to know beforehand.
This article contains heavy spoilers from theDemon Slayermanga; proceed with caution.
8Nezuko’s Immunity To Sunlight Changes Everything
The Power That Turns The Tide Of Battle
An iconic moment inDemon Slayerwas when Nezuko survived being in the sunlight and was able to finally talk to her brother, Tanjiro. Nezuko becoming a demon was one of the main reasons why her brother became a Demon Slayer. Her breaking free from a demon’s inability to walk in the sun caught Muzan’s eye.
Muzan is more than eager to find Nezuko now, as her ability could be what stands between him and his idea of perfection. If Muzan gets hold of her, it could cause a big problem. She could be a key game changer, as her power can make or break the Demon Slayers.
7Muzan’s Near-Immortal Regeneration Makes Him Terrifying
The Demon That Just Won’t Die
Muzan Kibutsuji, the first and original demon, has a terrifying ability to regenerate quickly. One incredible display of this ability was when Kagaya Ubuyashiki, the leader of the Demon Slayers, set a suicidal trap for Muzan, who finally found the whereabouts of his home. As mind-blowing as the trap was, Muzan came out alive and regenerated quickly. Eventhe Nichirin sword, which is used to kill demons, is not capable of defeating him by simply beheading him.
With over a thousand years of experience, his superb abilities, and the Upper Demons with him, the Demon Slayers defeating Muzan feels nearly impossible. Muzan is not an ordinary demon, so the Demon Slayers need to be prepared to face their most difficult opponent ever.
6The Mysterious Power Of The Demon Slayer Marks
The Awakening Of A Secret Weapon
From the very first episode, Tanjiro has always had a mark on his face. It was only recently that viewers learned that it is a Demon Slayer Mark. Inthe Swordsmith Village arc, Muichiro and Mitsuri, both Hashira, joined Tanjiro by meeting the conditions required to activate the mark.
Fans are curious and left wondering whether the remaining Hashira will also awaken their markings and join the likes of Tanjiro in the Infinity Castle arc. The Demon Slayer Mark boosts the owner’s strength, which should be extremely useful since the Slayers are to face their arch-enemies.
5The Hashira’s True Strength Will Finally Be Unleashed
No Holding Back This Time
Until now, the anime has only hinted at the Hashira’s true potential, fromRengoku’s tragic duel with Akazato Tengen’s face-off in the Entertainment District and the most recent fight in the Swordsmith Village. While each one gives a glimpse of the Hashira’s individual brilliance, fans have not seen the strength of all the Hashira combined.
The Infinity Castle arc will change that. With the surviving Hashira gathered in the castle, their strength will be tested like never before. In a battlefield designed to give the demons the upper hand, the Hashira will need to unleash their strongest techniques, synchronize, and evolve to survive. It’s no longer about personal glory—it’s about collective survival.
4Zenitsu’s Thunderous Calm In The Face Of Death
Stillness That Hides A Storm
Zenitsu has always been a fun and jovial character. He constantly panics in the face of danger,yet displays immense power when fightingin his sleep. After receiving a mysterious letter, his demeanor changed. Whatever was written in the letter has clearly shaken him, and he is showing an unexplainable calmness.
Viewers have seen the scared Zenitsu and the unconscious warrior, but this new version is different and exciting. Zenitsu shows no fear as he enters the castle, which is unusual for this character. As the Infinity Castle arc approaches, this composed Zenitsu may reveal a level of strength he’s never consciously accessed before.
3Nezuko Is No Longer Fighting Beside Tanjiro
A New Solo Battle Begins
Watching Nezuko grow has been one of the most rewarding parts ofDemon Slayer. From the quiet girl who spends most of her time in a box to the fierce demon fighting beside her brother, her journey has been wild. And Tanjiro? He’s grown too—every fight, every scar, all because he wants to protect her.
But now, things have shifted.Nezuko can’t fight by his side anymore—she has to hide from Muzan, and that changes everything. Tanjiro’s going into battle without her strength beside him. It’s just him, his blade, and the hope that he makes it back to her.
2Muzan’s Growing Desperation Is Pushing Him To Madness
A Relentless Obsession With Immortality
For Muzan Kibutsuji, it seems everything is starting to fall into place. He finally located the Demon Slayer Corps Headquartersand killed Kagaya Ubuyashiki, the leader of the Demon Slayers. To top it off, Nezuko’s conquering of the sun has opened up a nice opportunity for him to reach his goal. If everything works out for him, he will attain full immortality.
As success is seemingly within his reach, Muzan becomes more and more obsessed. This makes him scarier than he has ever been. As the Infinity Castle approaches, Muzan’s desperation will intensify, making him unpredictable and very dangerous.
1The Infinity Castle’s Reality-Bending Nature Is A Nightmare
Muzan’s Battlefield Is Designed To Trap The Demon Slayers
The first peek viewers got of the Infinity Castle was in season 1 when Muzan summoned his Lower Moons. The Castle defies the laws of physics as it is constantly changing and feels like an endless maze. Walls can move, rooms can shift, and gravity can change its direction.
Thestructure of the Infinity Castlemakes it not only the location of the battle but also a weapon that Muzan can use against his opponents. Its complex passages make it unimaginable to escape without defeating the one controlling it. The Demon Slayers have entered a very dangerous trap where they face not only Muzan, but also the environment itself.
