Tanjiro Kamado, Nezuko Kamado, Genya Shinazugawa and Mitsuri Kanroji vs Hantengu

Tanjiro Kamado, Nezuko Kamado, Genya Shinazugawa and Mitsuri Kanroji vs Hantengu is a battle that takes place in the Swordsmith Village, between Demon Slayers Tanjiro Kamado, Nezuko Kamado, Genya Shinazugawa, and the Love Hashira Mitsuri Kanroji against Upper Rank Four, Hantengu.

Prologue
Following the death of Upper Six demons Daki and Gyutaro in the battle in Yoshiwara, Muzan Kibutsuji summons the remaining Upper Ranks to the Infinity Castle. He relays his anger over having a change amongst their rankings, which had not happened in 113 years, and he admonishes them for their continual failure to either kill the Ubuyashiki family or find the Blue Spider Lily. Upper Five Gyokko then informs Muzan of information he had discovered in an attempt to appease him, and deeming the intel worthwhile, the Demon King orders him and Hantengu, Upper Rank Four, to infiltrate the Swordsmith Village.

Two months after defeating the Upper Rank siblings, Tanjiro Kamado regains consciousness from the severe injuries he had taken in his ordeal. After a week of rehabilitation, he inquires about his Nichirin sword, only to be informed in a letter given by Kiyo Terauchi that his swordsmith, Haganezuka, had refused to make him another one. He travels to the Swordsmith Village with Nezuko to negotiate a weapon to be made for, and subsequently meets the Love Hashira Mitsuri Kanroj i, as well as Genya Shinazugawa, who he recognizes as the third male survivor in his Final Selection. He then enters a nearby forest and meets the Mist Hashira Muichiro Tokito.

Leaving a pot in the open for someone to find, Gyokko sucks a swordsmith inside and spits him out after tasting him, confirming that they have entered the hidden village. He hopes that destroying the village will cripple the Corps with a lack of weapons. Elsewhere, Hantengu, fearful of Muzan's wrath, resolves to kill everyone inside to appease him. Muichiro meets with Tanjiro in a house to discuss their swordsmiths. The Mist Hashira, though initially uncaring and aloof, warms up after seeing Tanjiro's kind and helpful nature.

The coward's true strength
Hantengu enters the room and crawls towards the two. Hiding his engraved eyes, Muichiro and Tanjiro do not see what rank he is but immediately know he is an Upper Rank demon. Muichiro attacks the demon with Mist Breathing, Fourth Form: Shifting Flow Slash, though he misses when Hantengu leaps to the ceiling. Using a sword provided to him, Tanjiro uses Hinokami Kagura: Sunflower Thrust to hit Hantengu, but the Upper Rank is able to quickly dodge the attack and land on the floor. Nezuko joins the battle and kicks Hantengu in the hip, stunning him with the impact and allowing Muichiro to quickly behead him. However, knowing of Daki and Gyutaro's unique immunity to decapitation, Tanjiro reminds Muichiro to stay on guard.

Hantengu's severed head suddenly forms a new body, whilst his old body becomes a new demon entirely. As Muichiro attacks the demon in front of him, it uses a maple leaf-shaped Uchiwa and blasts Muichiro out of the house with a gust of wind, while Nezuko and Tanjiro struggle to hold on.

The uchiwa-wielding demon, Karaku, talks to the other demon, Sekido about his joy seeing the Demon Slayers struggle in his wind, but the former only voices his anger at having to be combined with him to begin with. Sekido uses his Khakkhara to summon a burst of electricity that incapacitates the Kamado siblings.

"It's Genya!"
From the roof top behind the demons, Genya suddenly appears and shoots them with a shotgun loaded with Nichirin steel shot, decapitating Sekido but only partially severing Karaku's neck. Genya rushes to the floor and finishes beheading the demon with his sword, only to be warned by Tanjiro to avoid beheading them. Sekido and Karaku heal instantly, and their old bodies become two new demons, now totalling four Upper Rank opponents. Tanjiro is grabbed by the winged demon, Urogi, and flown into the sky; before he is taken away, he tells Nezuko to assist Genya, who is concurrently being attacked by the Yari-wielding demon Aizetsu. Genya is unable to dodge the demon and is stabbed in the chest. Tanjiro tries to attack Urogi but is hit by a deafening sonic shriek, only freeing himself by cutting off the demon's leg. He falls into the forest below and lands hard on the ground, but the leg still attached to him forms a new head. Tanjiro cuts it in half, only for the halves to form two mouths and hit him with the sonic attack again. However, he notices that the attack's strength has weakened, realizing the clones all have to share one strength. The healed Urogi slashes Tanjiro with his talons but simultaneously has his head split by the Demon Slayer.

Karaku has Nezuko in his hold; Sekido irritably tells him to quickly kill her but the relaxed demon wants to savour the moment. Genya, while still pinned by the weapon, shoots Aizetsu in the head, but the demon pulls the Yari sideways, cutting through Genya's body. Genya seemingly loses consciousness while saying the Amida Sutra, but when Aizetsu tries to kill him, he suddenly appears behind the demon and tries to behead him. However, Sekido stuns him with his lightning, though he is confused at how Genya is surviving such horrific wounds. Having had his fun, Karaku kicks Nezuko and drives his leg through her body. He informs Sekido that he will rip off her limbs and he can use his lightning to kill her, to which the angry demon states that it was his initial plan all along. When Karaku tears off her hand, he is suddenly kicked in the head by the young demon; her blood sprayed all over him then ignites, startling him and Sekido. Holding his hand wielding the uchiwa, she blasts Karaku with his own wind. When she attempt to do the same Sekido, he blitzes her and stabs the Khakkhara into her neck, before generating lightning to stun her.

In the forest, Tanjiro struggles to fight Urogi's speed and the thick tress obscuring him. He sees the building with Nezuko and Genya inside in the distance and moves to it; when the demon attempt to swoop in and slash him, he anticipates the move and stabs Urogi in the mouth. They both land back inside the building, where Tanjiro sees Nezuko being shocked. Sekido tries to shock him as well with his Khakkhara but Tanjiro uses Urogi's severed foot to prevent the lightning being channelled. He then slices Sekido's tongue, having realized that when their tongues are injured, they heal slower. Tanjiro uses the foot to remove the Khakkhara imbedded in her; he is in turned saved when Sekido attempts to stab him behind the neck. Nezuko grabs it before it can go deeper into her brother and sets Sekido ablaze with her Blood Demon Art.

Suddenly, he sees Karaku in the sky; having healed and now wield a new uchiwa, he hits Tanjiro and Nezuko with a powerful blast of wind, knocking them unconscious with the sheer pressure, leaving a maple-leaf shaped indentation in the floor. Tanjiro regains consciousness and is grabbed by Nezuko to avoid another burst of lightning from Sekido. Urogi tries to swoop in and slash them but the siblings duck out of the way. Sekido orders Karaku to destroy the building, which he does by summon a gust of wind in the interior, blowing up the entire structure. Tanjiro is unharmed but Nezuko is pinned beneath rubble.

Recurring memories
Tanjiro tries to remove the debris but is shocked to see Nezuko grabbing his sword by the blade. She cuts her hands along its edge, coating the sword in her blood, which she ignites. Tanjiro watches in amazement as the steel begins to turn bright red, similar to the memories he saw of the unknown swordsman. Urogi, Karaku, and Sekido watch as Tanjiro walks towards them by himself, but only Sekido notices that his weapon is now red, similar to the blade of the swordsman who nearly killed Muzan. As the scar on his forehead grows into a fiery mark once more, Tanjiro unleashes Hinokami Kagura: Sun Halo Dragon Head Dance, instantly slicing through the three Upper Rank clones in one fluid move. He recalls the moment when he fought Gyutaro and how he had suddenly gained the strength to cut off his head, how his breathing and body felt like it was burning.

To his surprise, he sees Genya close by; Genya had managed to pin Aizetsu to a tree with his Yari and beheaded him. When he turns his head however, Genya now has a monstrous appearance, his eyes with black sclera and fangs in his mouth. Urogo and Karaku are shocked at Tanjiro's attack and fearfully believe that their regeneration has stopped, only to be told by a furious Sekido that it is simply slower.