For years, the Niflheim Empire and the kingdom of Lucis have engaged in ongoing conflict. The empire, seeking dominion over the world of Eos, sets its sights on the coveted Crystal safeguarded in Lucis' capital, Insomnia. To shield his realm from the encroaching threat, King Regis Lucis Caelum CXIII harnesses the Crystal's power to erect a mystical barrier around Insomnia. Complementing this defense, Regis forms an elite fighting unit called the Kingsglaive, tasked with defending the kingdom's borders by drawing strength from the king himself. Among these skilled warriors is Nyx, known as 'The Hero' for his bravado and altruistic spirit. Yet, Nyx's hubris leads to insubordination and demotion after defying his superior's commands. Assigned to gate duty, Nyx's routine existence takes a turn when rumors surface of Regis' intent to broker a peace treaty with their longstanding foes.