: Rengoku guides Tanjiro through a total concentration breathing technique to stop his internal bleeding, showing the vast gap in mastery between a Hashira and a novice.
Introduced as a terrifying new threat, demonstrating the overwhelming power of the Upper Rank demons. Kimetsu no Yaiba: Mugen Ressha-hen Episode 6
Watch the intense introduction and battle of Akaza in this episode summary: Akaza - Demon Slayer Mugen Train Arc Episode 6 Reaction YouTube• Nov 29, 2021 : Rengoku guides Tanjiro through a total concentration