Aether

The Aether can be thought of as a mix between the spiritual realm and the astral plane of Shattered Wilds. Every living creature has a Spark in the Aether, that is attached to their physical body. Sentient Sparks attached to physical bodies are called Souls. The gods (called Proteans) are essentially pure souls, that have fully unbound from the material plane and therefore have complete reign on the Aether. While they have no physical body, they can manifest as a physical avatar, but unlike a creature body and Spark that are bound together, the Protean can simply abandon any avatar at will. Divine magic involves channeling forces through the Aether, either of Proteans or your own.