According to the mythology of both the Genosian and Dessian religions, the Seven predate both the Sun and Moon. Indeed, they predate the very stars in the sky. They were creatures of nothingness, that existed before time and 'stuff' invaded their realm.
The Seven are primordial gods who predate the coming of He Who Came First and The Four Great Old Ones. This is agreed upon by all of the Celestial religions (Genosism, Dessianism, and of course Seven Worship.) Their realm of perfect timelessness was shattered by the coming of light, and according to Zellish mythology, each of the Seven was forced to take on a form and a name, where before they would not have had to.
When the flesh of the Four contacted He Who Came First's light they were destroyed, but the Four Great Old Ones cast shadows, and these shadows became The Seven.
The coming of the Sun and Moon illuminated them, and so destroyed much of what they once were, by forcing them to take shape and character. The Seven were of course, really upset about this, so they trolled the invading gods by creating life, in the form of the Chaos Dragons, which began a cycle of events that resulted in all life that exists today on Mundus.
They also conspired with Dessia who used one of their names as a curse (despite not knowing who they were, or even that they existed,) giving them the power to strike Genosus in the back, and wound him so severely that he fell out of the sky.
Now, deprived of their true forms, The Seven have become independent entities with strange and confusing minds, motives, and realms of power. They created life by crafting the Seven-Times-Seven Chaos Dragons, and gave them life and sentience, but no purpose. The Dragons were thus in anguish, and flew about Mundus, and then laying it to waste and heating its oceans, causing life to spark in them where the kiss of Chaos met the waves.
Thus, by creating life, The Seven trolled Genosus and Bocanadessia, children of He Who Came First, who were charged with keeping everything exactly the same as it had been at the beginning of time. In this way, they got their revenge.
Eventually, the Dragons of Chaos were slain by Genosus and his chosen agents. Their corpses fell into the sea, and from those corpses, the Zells emerged, riding the boiling waves upon their great mother-ships.
The Zells have sailed ever since, and venerate The Seven as their direct creators.
Or, so the story goes, anyway. Each tribe of Zells worships one of the Seven, based on which of the Chaos Dragons they believed to have sired their line.
The Seven have, since then, been on and off enemies and allies of the two Celestial Gods. Their nature is so divergent from that of Genosus and Bocanadessia that there isn't really cooperation, just mutual dislike.
- Yog-Tesshecht, Cliff-Eater, The Swallower of Stars, Master of Matter.
- Yog-Boma, Lord Tattersails, Fleshmover, Prince of Pain.
- Yog-Chiii (Chee-ee-eye), Mister Quiver, King of Knowledge, God of Regret.
- Yog-Zhzhdon (Zhee-zee-don), Prince Scrimshaw, Hullcrafter, God of Art, Wisdom, and Madness.
- Yog-Sethis, Lord of Silence, The Whispering One, God of Secrets, Murder, and Love.
- Yog-Dakon, Lord of Seared Flesh, The King of Hedonists, God of Desire and Satisfaction.
- Yog-Yalang, King of Fleets, Purveyor of Alliances, God of Failure.