Hayate Musashi (in Japanese: ハヤテ・ムサシ) is the estranged son of the legendary Joe Musashi and the protagonist of the Japanese version of the Shadow Dancer; the Secret of Shinobi. Hayate's father sent him to live with Dick Kato when Joe decided to go rogue to give his son a better life. Adopted by Dick Kato, Hayate grew into a young man with a good heart and resolute spirit. When his adoptive father was killed by Asian Dawn; a syndicate that sought to fill the void Neo ZEED had left, Hayate went with his faithful dog Yamato to seek revenge.
Hayate is a well built man who wears a white ninja armor with a sleevless red chainmail shirt and black pants. He wears a shinobi kabuto over his head and a cloth mask over his lower face to hide his identity. He carries with him a sword, possibly the Hazy Moon Blade of the Oboro Ninja.
In the winter of 1977 Japan, Iga province. Joe Musashi and his wife Naoko take their son Hayate to flee the Oboro Village. Joe Musashi had decided to become a rogue ninja for the sake of their only son, not wanting him to deal with the torments of the Shinobi World. However, by the time the reach the ship headed for America, It is revealed only two can go, and so with a heavy heart, Joe sent wife, his little boy, Hayate, and the little ninja dog Yamato, to go to America to live with a family friend. This would be the last time Hayate would see his father's face.
In the spring of 1978 Naoko and Hayate would be found by Dick C. Kato, a Kobudo Dojo teacher. who found them in the middle of his jogging routine. The mother was already gone, but Hayate and Yamato were safe, and in the little hands of Hayate, Dick found shuriken. Surprised to have found a Ninja child, Dick took Hayate and Yamato, and raised the one year old boy as his own son.
By the summer of 1997, Hayate, who had trained with Kato, grew to be an amazingly talented martial artist, as Ninja were naturally not only familiar with mystic ways, but martial arts as well, leading Kato to think he really was a Shinobi's child.
But while they lived in peace, a mysterious terror group had butchered countless innocents in the city. Some of its members were ninja, and the fear and terror intensified. One day, while Hayate was returning from practice, he came across an injured Kato, who had been attacked by a mysterious group. Kato, the man who mercifully took him as his son, had died. Carrying the sorrow, anger and rage within him, he found a keepsake of his real father; a Ninjato. It was then that Hayate's dormant Oboro Ninja Blood had awakened. Hayate marched on to avenge his adoptive father, with the ninja dog Yamato by his side.
Hayate would cut through a swath of terrorists, and would fight until he came across the monstrous chief of Union Lizard; the mutant who took Kato's life. With rage burning, Hayate focused all his skills destroying the monstrous villain until at last the battle was over.
Looking back with his dear dog Yamato, at the Statue of Liberty, Hayate departs to face his destiny as a Ninja.