We can shake out Pantheon history before we start, but the way I have it written was that Ventu was the first deity and Vael and Nys, Aroesus, Svanus and Sileon are children of his. He was overthrown when he decided to cull humanity because they'd become too upstart and Aroesus and Svanus, at least, weren't willing to let their creations be destroyed out of sold old god's sense of being a high and mighty dick. (Svanus is dead; Noxious' character is his daughter and Svanus and Aroesus didn't see eye to eye at the end anyway)

There's room for others, and perhaps in the wake of Ventu's death, a number of beings tried to rule in the chaos; it's possible, for example, that Aroesus didn't take the mantle of rulership immediately.

Edit: Between the rule of Ventu and Aroesus' triumph, I have it now written that there were other deities and pantheons that took over before Aroesus finally did. So now we explain how the other pantheons existed and so forth.

Further Edit: I'll handle the rest of stuff today after I get home from work. 6am start time. ;)

Last edit: Here's what I have for Pantheon history and we can wiggle it around (I'm willing to modify) to work with.

[quote]Ventu was a primal deity of fire, creation and destruction, but also the absolute ruler of the world. He was content to rule the cosmic forces without doing too much with them, being a simple being of simple tastes. He sired, upon the stars, other beings, including Aroesus and Svanus, who were of a more creative, cultivating bent. They created and Ventu destroyed before the creations could get out of hand and his children become empowered. His final child was Sileon, who was like Ventu in so many respects that Ventu favored this youngest over all. And yet, Sileon stood in awe of the things he didn't entirely understand, and learned from watching his elder siblings as they moved through the world and created things, including fickle humanity and spawned their own progeny.

The time came again when Ventu was inclined to destroy the works of his children and the other things that came to being in the world, and that was when Aroesus and Svanus (and others) rebelled against them. And it was Sileon, left free, trusted, who Ventu thought understood the best, who freed them from their imprisonment in Sharzunates, who decided that he could not bear to see the works of his siblings, whom he loved, destroyed.

Aroesus and his host organized, a thing unknown to Ventu, who ruled in singular absolutism, and revolted against the king of the gods. After the death of Ventu, there were other mighty beings that tried to take Ventu's place in turn and Aroesus' Pantheon fought them under his leadership. The other siblings found roles in the court of Krona that befit their talents; but Sileon inherited the raw strength and primal of his sire, and became a force of destruction akin to his father, though he voluntarily put himself into slumber in a mountain so that the creation might thrive, electing to hold himself aloof until needed. From time to time, Aroesus would call upon Sileon to assist in maintaining the order of Krona, to bring other deities and beings into the order, and for this, he would be awakened and unleashed upon enemies. Even if they were powerful, they were brought low by the combined cooperative might of the sons of Ventu.[/quote]