During the Cosmo War, in the First Era, the Avatar of the God of the seas was corrupted by an ancient Demon Lord, Draiken Zestirot the Animancer Master, just before being banished into his Astral Domain.
Corrupted by the Demon Lord, the Avatar of Holmuran acquired consciousness and believed that he was the true god of the seas, declaring war to Holmuran people and trying to conquer the Sunken Kingdom.
During the second Era, the Avatar of Homuran used his Animancer powers, inherited from the Demon who had corrupted his soul, to break and mix the souls of the sea folk to create a superior race to subjugate them all, the Slathaai.
By accomplishing this task he consumed his soul almost entirely, falling into a sleep from which he could only awaken after absorbing enough souls to re-fuel his divine spark.
This is the reason why after centuries the Slathaai, masters of soul manipulation, allied with the Tyrant God Tialevor to help him in his battle against the other gods. During the final battle, the Slathaai channelled enough souls to their sleeping false God, now woke up and ready to help his children to conquer both the Depths and the Surface!