The Greatest Slayer
Yoriichi is the only swordsman to push Muzan to the brink of death, using the original Sun Breathing in its purest form.
Twin and Rival
His relationship with his twin, Kokushibo, defines both their fates—one as a legend, the other as a demon.
Legacy
His techniques are preserved only in fragments through other breathing styles, yet his influence shapes every slayer who follows.