Demon Slayers vs Muzan Kibutsuji: Part 2

Demon Slayers vs Muzan Kibutsuji: Part 2 is a battle between Demon Slayers Tanjiro Kamado, Zenitsu Agatsuma, Inosuke Hashibira, Kanao Tsuyuri, Hashira Giyu Tomioka, Mitsuri Kanroji, Obanai Iguro, Gyomei Himejima, Sanemi Shinazugawa, and Demon Yushiro along with the remains of the entire Demon Slayer Corps against Demon Lord Muzan Kibutsuji. It occurs immediately after the Infinity Castle is destroyed.

Prologue
Kiriya Ubuyashiki realizes that Tamayo couldn't endure long enough to hold Muzan down and the medicine that both Shinobu and her concocted was unsuccessful in reverting Muzan back into a human. Kanata informs Kiriya that the first team of Demon Slayers have arrived where Muzan's flesh cocoon is resting and a second group is following them. Kiriya immediately orders her to tell the Demon Slayers to stay away from Muzan until all the Hashira arrive. Multiple teams of Demon Slayers surround the capsule of flesh that Muzan is residing in. A Demon Slayer hears an order from a Kasugari Crow that all the Demon Slayers should standby and not engage until the Hashira arrive as they have no idea on what can happen. Suddenly, Muzan emerges from his flesh cocoon with a brand new appearance, his hair being far longer and being silver white due to his accelerated aging. He also has numerous jaws all over his body with sharp white fangs used to consume human flesh and blood, and is holding Tamayo's disembodied head on his right hand. Muzan massacres the dozens of Demon Slayers currently within his vicinity as they try to retreat from his location. Kiriya attempts to order them through a Crow for them to fall back. However, Muzan murders and consumes all the Demon Slayers within their groups and beheads the Kasugari Crow that gave the orders to retreat.

Muzan notes that due to him aging over a millennia, he has lost the desire to taste food however due to him starving for taking the force of the Ubuyashiki explosion and using his energy to nullify Tamayo's drug he now adores the taste of flesh and blood. He compliments Kagaya for "deliberately" bringing him humans to feast and to regain his strength and stamina. He even wants the new successor to bow down so he could possibly turn him into a demon since practically all of his subordinates are killed. Back at what's left of the Demon Slayer Headquarters, Kiriya commands his two younger sisters to make the second troop of Demon Slayers retreat and keep their distance away from Muzan as he'll only regain more strength and stamina from consuming more flesh.

Muzan lifts Tamayo's disembodied head and mockingly points out that her "drug to turn back into a human" had no subtle change to his body. He also imitates her words that he'll fall into hell and that hundreds of people have spoken similar words to him and that it has never happened once. Tamayo sheds tears and begs Muzan to give back her husband and children, in which he bluntly tells her to die and head to her family that "she" killed. Thus, Muzan crushes Tamayo's skull and consumes her blood and cells. Due to Yushiro's Blindfold being within the vicinity, Yushiro immediately loses his balance and topples over onto a wall with nearby Demon Slayers questioning whether he is alright. Muzan continues massacring more and more Demon Slayers within his path continuing to gain more stamina. Kiriya screams and begs the Demon Slayers to fall back so they can not give Muzan more strength and sustenance along with Tamayo's sacrifice to not be a waste. Muzan notes that every single member of the Twelve Kizuki was of no use to him and that he'll slaughter the Demon Slayer Corps himself.

Battle
After all the Hashira, Inosuke and Zenitsu were knocked down by Muzan Kibutsuji, Kanao remains the sole fighter in the field. She tries to will herself to fight, and just as she prepares to defend against the Demon Lord's incoming strike, Tanjiro Kamado regains his consciousness with the help of Yushiro's medicine, and uses his newly mastered Sun Breathing: Beneficent Radiance to cut off Muzan's arms and rescue Kanao. The two converse, Muzan mocking Tanjiro's wounded appearance, while the Demon Slayer, enraged at his allies' injuries, calls on the Demon to end their long-standing feud.

Aftermath
Muzan's defeat while significant, would prove to be a costly victory for the Demon Slayers, leaving scores of members deceased, dozens mauled and heavily injured and many on the verge of death.

Tanjiro turns into a Demon, starting a new battle.