Aeterna Noctis

Unnumbered years ago, the supreme god Chaos created the Universe and the world of Aeterna. After populating it with different races and creatures, he appointed powerful rulers to govern them and show them the way. But soon they turned against their Creator, seeking to take the world for themselves; and gathered their subjects in two groups that fought each other -- and thus gave rise to war, death and hatred.

The all-powerful Chaos was angered, and in His terrible wrath, He cast a terrible curse upon the rebellious leaders. He named them King of Darkness and Queen of Light, and condemned them to keep fighting each other forever, until the end of time. Not even death would free them from this doom, for Chaos granted them the Gift of Immortality -- so that even if one managed to defeat the other, they would be reborn, and regain their powers to continue their eternal war.