The Sunrise Countdown Arc is the final arc of the Demon Slayer manga, occurring after the Infinity Castle Arc, where the Demon Slayers launch their all-out assault on Muzan Kibutsuji, aiming to defeat him before dawn breaks, featuring Tanjiro's mastery of Sun Breathing and the ultimate battle to end the demon curse. It details the final showdowns, including Tanjiro battling Muzan and the remaining Hashira fighting powerful demons, culminating in the ultimate goal of reaching Muzan and overcoming him as the sun rises.