BAKI-DOU: The Invincible Samurai

BAKI-DOU: The Invincible Samurai is an action sports ONA that premiered on February 26, 2026. The series consists of thirteen episodes and concluded its run during the winter 2026 season. This installment introduces Musashi Miyamoto, history's legendary swordsman, into the underground fighting arena where weapons are finally permitted. The clash between traditional blade mastery and the raw martial prowess of Baki's world creates an entirely new competitive landscape.

The premise pits Musashi against the underground's elite fighters, including Doppo Orochi, Goki Shibukawa, and Sea King Retsu, in battles where the stakes are absolute. Unlike previous tournaments that focused on unarmed combat, this season fundamentally changes the rules by allowing weapons into the ring. The series appeals to fans of high-stakes martial arts action who want to see how peak hand-to-hand fighters fare against a master swordsman.

Since the series has finished airing its complete run, all thirteen episodes are now available to watch. The ONA format means this story was released as a complete package rather than airing weekly, making it accessible for those looking to watch the entire arc in one sitting or at their own pace.