Crown Prince Tatsu is the only son of the Emperor Yoshiro and thus his second-in-command. The Western-educated Tatsu is the one responsible for the modernization reforms of the Imperial army, and the development of much of their new technologies, including nanotechnology and the Rocket Angels, as well as the Shogun Executioner. A hotheaded and ruthless figure, Tatsu often clashes with his more stoic and conservative father, believing that victory against the Empire's enemies will not come from intimidating them into submission, but on the battlefield. Tatsu also places greater faith in the Empire's technology than his father does, and believes that destiny is not a blueprint to follow, but rather something that can be made through bold actions and force of will. Still, despite their disputes, Tatsu remains very loyal and dedicated to his father, and defers to his judgment in times of crisis.