Yorozu Genkurou, a skilled warrior, navigated through a dim forest with his massive sword, causing fear in his foes. Suddenly, he noticed a spaceship falling from the sky. Confused by this strange occurrence, Yorozu soon realized that the unidentified adversaries he had been fighting were actually extraterrestrial beings. These space creatures had arrived on Earth to locate three powerful Orichalcum relics, including Yorozu's sword. Thus began an intense pursuit.