Ataraxis' Crystal, in order to stop the endless War of Ruin that all but destroyed the World of Veil. These Ruin Lords, once they had accomplished their goals, created Cities as a beacon of light and hope for the new world they had created.
During the story of Heroes of Ruin, it is thought that once Ataraxis' Crystal is charged at all three of the Ruinscars then Ataraxis will wake from his slumber. However it is revealed that Rigel, the Archmage of Nexus, used the Hero and Prince Solon to charge it for his own means - to become King of Nexus. It was revealed soon after the defeat of Rigel that he was just a puppet of Prince Adrian, who wanted the Crystal to turn himself into an all powerful Ruin Lord and take control of Nexus and the World of Veil. However, Prince Solon intervened during his transformation process, causing him to become a deformed Ruin Lord.