Ability
Ganryū-jima. Your ATK is compared against the rival's ATK, not their DEF. The card Musashi defeats doesn't go to the graveyard: it is banished from the match — and every copy of it with it, whether in hand, in the deck or already buried.
The myth
Born around 1584 in the twilight of the Sengoku wars, Miyamoto Musashi killed for the first time at thirteen and never lost again. A masterless rōnin without land or lord, he crossed Japan testing himself in more than sixty duels: alone he broke the Yoshioka school beneath the pine of Ichijō-ji, and he cut down Sasaki Kojirō on the island that now bears the loser's name. When the country finally quieted and his trade ran out of enemies, he withdrew to the cave of Reigandō and turned the blade inward: there he wrote the Book of Five Rings, painted shrikes in ink, and set down twenty-one precepts of solitude. He died in 1645, leaving two swords, a brush, and a doctrine no one has yet exhausted.