Demon Slayer Manga Chapter 167

Two Demon Slayer marks flare to life in the same battle. Gyomei and Sanemi, fighting side by side, push their bodies past every limit as the striped patterns spread. Their weapons move faster, strike harder, and begin to corner a demon who has not been cornered in centuries.

But Kokushibo has survived the entire era of the mark before. He calmly recalls that marked slayers die young, and he shows no fear at all. His blade grows branches of smaller blades, and the crescents multiply into a storm that fills the hall from wall to wall.