With the Upper Rank demons Hantengu and Gyokko defeated, and Nezuko conquering the sun, the final confrontation with the Demon Lord Muzan Kibutsuji looms closer than ever. To bolster the strength of the entire Demon Slayer Corps, the remaining Hashira implement an intense, specialized training program. Tanjiro Kamado, along with his friends Zenitsu Agatsuma and Inosuke Hashibira, participate in these grueling sessions led by different Hashira, each focusing on enhancing specific skills like stamina, flexibility, speed, sword technique, and muscle reinforcement. This arc showcases the Hashira's unique personalities and training methods while building anticipation for the impending ultimate clash against Muzan and his remaining forces.