Saga

Saga (サガ) is the 'main antagonist' of the fifth movie. He's a childhood friend of Zoro's (both went to the same dojo together) and Maya's friend and possible love-interest. The real Saga is a friendly, honorable, and ambitous young man. He fell into depression after losing use of his right arm, but was brought out of it by Maya, whom he met when he drifted to her island. He was accepted into her village and later fought alongside them when they were attacked by pirates. During the fight, he and Maya ran into the shrine that housed the Seven Stars Sword. He fell under the evil influence of the sword when he used it out of desperation to save her from the pirates.

The sword possessed Saga to try to rise to full power and bring darkness to the world. Saga took over and possessed an entire Marine dojo to help in the quest.