Urokodaki coaches Tanjiro for the final selection, in which he must strike demons in the neck with a special nichirin sword. After training with Makomo, Tanjiro can now use his sense of smell to find an “opening thread” that runs from his blade to a demon’s weak point. Urokodaki admits he never intended for Tanjiro to split the boulder, as he doesn’t want to see another pupil die. He gives Tanjiro a fox-themed “warding mask,” the kind Sabito and Makomo wear. He promises to look after the sleeping Nezuko while Tanjiro is gone. As Tanjiro leaves, he asks Urokodaki to give his regards to Makomo and Sabito; Urokodaki is astounded that Tanjiro knows the names of his deceased students.

Tanjiro goes to Mount Fujikasane, where the final selection is being held. Demon slayers have trapped demons on the mountain, kept there by a border of blooming wisteria, which demons hate. Whoever survives on the demon-filled mountain for seven days will pass the final selection.

Tanjiro immediately encounters two demons. He smells the opening thread and uses the fourth form of his “total concentration water breathing”—a move called “striking tide.” He decapitates both demons. Tanjiro suddenly smells something rotten.