Thousands of years ago, the four races of humans, demons and monsters fought. Tang Nuoyi, the strongest of the human race, and Zixue, the leader of the demon race, fought against the eight demon tribes and the king of the monster race in the Black Prison Mountain, and finally died together. Since then, the war between the four races that lasted for decades has finally ended. The two groups of monsters disappeared, and the demon race and the human race established friendship. The peace lasted for thousands of years until a thousand years later...