The Great Devourer
"Before the sun, before the stars, before sea or sky or stone, there was the Devourer of all, and all in their time shall be consumed. It is the great and noble purpose of existence to sustain the Great Devourer" - an excerpt from the Litany of the Devourer
Deep beneath the sea there is a being which may have existed since before the world formed. Its body is embedded in the sea floor, and its mouth gapes open, drinking in the water and all that lives within it. It is the Great Devourer, and it consumes the body, mind, and spirit of all who come before it.
The Devourer is enormous. Most of its body is encased in the bedrock, leaving only the head and several tentacles visible to observers. Even so, the creature is a living mountain, measuring over two thousand feet from crown to the sea floor. Whales and other ocean giants can swim into the mouth of the Devourer, vanishing silently into the abyss within.
Food-in-Waiting
Around the base of the Devourer's neck is a community of people drawn from across the world who worship the Great Devourer and are awaiting their turn at blessed consumption. While they wait, they are free from all harm and ills - they need not breathe, eat, or sleep, and are sustained completely by the presence of the Devourer. Periodically one of them will be called to the maw of their god, to climb in and descend into oblivion, certain in the value and purpose inherent in their destruction. They are the Food-in-Waiting, and believe themselves to be the happiest and most content of all the thinking beings in the world.
The End
That which is devoured becomes one with the Devourer and no longer a part of this world. The Food-in-Waiting believe that in time, the Devourer will drink down all the sea, and enough of the land and creatures of the land that all shall crumble away from it. Then the Devourer will reach out across the sky, gathering in the sun and moon and stars, and all else that has yet to fulfill the purpose of existence. Only when all the worlds have become one with the Devourer will the function of the universe be complete. What happens after this is unknown, and to the Food-in-Waiting, irrelevant.
The Herald of the Devourer
The Sea-Goat is the servant and herald of the Devourer, who travels throughout the world to call those whose time it is to join the Devourer beneath the waves. Its call resonates with all those who do not know their purpose or question the meaning of life, and assures them of their importance to the grand scheme of the universe as food for the Devourer. You can read more about the Sea-Goat here.
Dream-eater
Some have attempted to approach the place of the Great Devourer through the Dreamlands, hoping to be able to learn more about this being and still being able to escape. But they soon learn that the Devourer consumes in all the realms, including the Dream, and their Eidolons are as much food to it as their bodies. All who are eaten by the Devourer experience Soul-Death, and no part of their being can return.
Yet another great reason to avoid the water! As if more were needed... ('^')
Ah, the Devourer will help out then, by drinking all the oceans of the world so there’s nothing left to fear! Truly, they are benevolent.