The Prophecy of the Chosen Ones

In 181 Aftermath a great Seer known only as Taika appeared before Rinnarl and foretold the downfall of the gods.

The lunar elf called the gods out for what they were - destroyers of worlds. She had Seen that they travel from one planet to another, cultivating life and then draining every last drop before leaving the world to wither and die as they move on. And so she had another vision, one that saw a dozen chosen and marked that would bring down the gods once and for all to prevent them from destroying Eralon and any further worlds.

Beyond that the details are vague, as only Rinnarl, her steward and a handful of guards were present for the actual telling. But other Seers have Seen the telling, and still more with various divination methods have been able to catch bits and pieces. Because of this the common folk know only that there will be twelve Chosen Ones with the power to bring down the gods, not understanding the history of the deities or the role they play in the world. Commoners also don't realize that it is only the gods magic that allows any but humans to exist, as all but humans, demons and the deities themselves came into existence only after the Great War and the huge amount of magic that settled into the world at that point. Without the gods over time all other sentient and magical races will cease to exist, simply fading out over time as fewer and fewer are born each year until there just are none left.