Katekyo Hitman Reborn!

The Strongest, Invincible Style (2x14)

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Gokudera's match concludes and the next battle is announced: the battle for the Ring of Rain between Yamamoto and Squalo. Hibari causes a commotion at the school as the battles have caused major damage to the grounds. Dino reveals that Squalo once defeated the Swords Emperor of the old Varia and that Yamamoto's Shigure Souen Style is useless against him. Yamamoto receives a shinai from his father that transforms into a katana only when using the Shigure Souen Style.