Kai A. Sanzyuda is a Master of the Empire. He is the son of Yami Kuroyamino and Airen Sanzyuda, grandson of Deiva Sanzyuda and half-brother of Seiju Kurayamino. He wields the Akage's Lightning (VI) and the Kuroge's Black Lightning (VII). He is a former member of The Black Tree, Team Kaiden,
Kai drafted himself into the Empire Military to seek out his father and avenge the death of his mother. He was put into a team with Jai Raider and. He is currently working with Octavius to seek out members of The White Tree.
Kai A. Sakazuki was born to Airen Sanzyuda and Ju Sakazuki in Kaiden, the Empire. When he turned 3 his father, who was revealed to be the mass murderer Scorpion, killed his mother in front of his eyes and disappeared. Kai became deeply unstable as a result of this. He lived with his grandmother, Deiva Sanzyuda, who taught him to deal with his pain and control his anger. She was unable to remove the cold remorse he felt for everything that happened.