The story on Atreia

Atreia, a world created by the god Aion, inhabited by humans and other creatures. Atreia is unique in design; however, after a devastating batter it was split into two halves connecting by the Tower of Eternity. Soon after creation, a race called drakens was designed by Aion as his servants upon Atreia. Beyond Aion’s expectation, the drakens eventually rebelled against Aion. What is worse, they began to attack the humans in turn. During the process of fighting against Aion, they gain more strength become more powerful and monstrous. The new name of Balaur was adopted. To better control the world, Aion created twelve Empyrean Lords, whose mission was to protect humanity and the Tower of Eternity from destroying.