New Mission

This is the twenty-sixth and final episode of the first season. It intercuts Tanjiro's recovery wrapping up at the Butterfly Mansion with a meeting Muzan Kibutsuji holds for the lower-ranked members of the Twelve Kizuki. Disgusted by their weakness, Muzan destroys most of them and grants the survivor a large dose of his blood. Tanjiro then sets out with Zenitsu and Inosuke for their new assignment aboard the Mugen Train.

Muzan culls the Lower Ranks

Inside a shifting fortress controlled by a biwa-playing demon, Muzan assembles the Lower Ranks, his appearance disguised. He reads their unspoken thoughts and kills them one after another, condemning their failure to grow stronger and their fear of the Hashira. Only the last demon survives by welcoming death, and Muzan rewards him with a heavy infusion of blood, ordering him to slay a Hashira and to hunt the Demon Slayer who wears hanafuda earrings.

Leaving the mansion

A Kasugai Crow delivers word of a mission tied to disappearances aboard the Mugen Train, where the group is to join Kyojuro Rengoku. Before departing, Tanjiro thanks Aoi and tells her that her help will travel with him into battle. He also gives Kanao a way forward, using her own coin to nudge her toward listening to her heart. At the station, Inosuke mistakes the train for a creature and headbutts it, drawing the police, before the trio climb aboard. Riding with them are the Flame Hashira and the surviving Lower Rank.

The first eyecatcher recreates a volume title page, and the second loosely echoes the opening chapter's cover. Several beats are anime-only, including the early reflex-test exchange, the crow's mission briefing, and the conversation between Kagaya Ubuyashiki and Shinobu. The manga also reveals that Tamayo and Nezuko stripped Muzan of his ability to read his demons' minds, a detail the adaptation omits, and it stages Tanjiro's collision with the Final Selection survivor differently.