Bakuzan

Secret Sword Bakuzan (秘剣縛斬) was Satsuki Kiryūin's special sword that has the ability to cut Life Fibers. It was split into Bakuzan Gako (tantō) and Bakuzan Kōryū (wakizashi) after Satsuki was defeated by Ragyō Kiryūin during The Great Culture and Sport Festival. After being broken, it was later revealed that the two halves of the sword can mimic the Scissor Blades' ability to nullify Life Fibers regeneration. Both swords were ultimately destroyed during the final battle against Ragyō.

Secret Sword Bakuzan
Secret Sword Bakuzan, a black-bladed katana that was primarily wielded by Satsuki Kiryūin. It's very powerful to the extent that it’s able to fight evenly with the Scissor Blade.

Bakuzan Gako
The Bakuzan Gako (縛斬・餓虎) is the shorter portion of the broken Bakuzan that has been reforged into a tantō. It was wielded by Nonon Jakuzure before she gave it back to Satsuki.

Bakuzan Kōryū
The Bakuzan Kōryū (縛斬・蛟龍) is a wakizashi reforged from the longer piece of the broken Bakuzan. It's wielded by Ira Gamagōri at first, and is later given to Uzu Sanageyama, stating that it's "more his thing". Eventually, Sanageyama gives it back to Satsuki after she was rescued.

Trivia

 * Satsuki's false toenails are made of the same material as Bakuzan.
 * Ira Gamagōri's final Goku Uniform's arm plating is as strong as Bakuzan.

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