Primordial

The Primordials are the apex lifeforms of the Chaos, either beginning as beings born to the Chaos itself that rose to power or elementals that grew in power enough that they could break their chains and ascend. They are the Chaos' natural equivalent to a god or, depending on their strength, a lesser god like the archfey.  Because of this they often have followers and worshipers that pledge loyalty, sacrifices, and even souls to them in exchange for boons and blessings.
Primordials are theoretically bound to the Chaos, but are able to freely interact with the Great Disc through the veil unlike the Gods of Order.  There is much debate in both academia and religious circles as to why this is, but many speculate it has something to do with the mutable nature of the Chaos itself.  It is difficult to block passage to something that is constantly changing its very being.  This ability has made Primordial Cults very popular on both the Disc and the Underworld.  And worshipers have successfully skirted around the restrictions of their gods by summoning Avatars of the Primordials on the Material Plane to enact their will.
For specific examples of Primordials, refer to Gods of Chaos.

Origin/Ancestry

Chaos