Arcane Genesis
In the texts of old, there we two: Order and Chaos, an they inhabited the Void. As they passed through the void their interplay and struggle dispersed aetherial energies which created the Great Expanse.
The Great Expanse is the plane of souls, ever changing and ever constant. As Time began, some souls grew stronger, eventually they crystallized into Aetherials, beings whose powers impacted existence itself. Order and Chaos received souls too; They took the names Aila and Lysar respectively, and they watched over the Aetherials, like ancestors watch their scions.
When the primordial maelstrom of aetherial energy calmed down, Aila gathered many of her close Aetherials and told them the secrets of creation; Aila told her secrets to eight Aetherials throughout all the infinite energies. Together, they were known as the Nine Divines.
Aila lead the Nine to forge a new plane of existence contained within the Great Expanse, a world of order for her chosen Aetherials to take pride in. The Divines channeled their energies into a well of eternity and mortality and formed the Arcanum, and each Aetherial contributed some part of their being for the mortal world.
Lysar despised the Arcanum, seeing it as a stain on the endless Great Expanse, wishing to exert his own dominance over the material world. Envious of the work of the Nine, he whispered dark promises to many Aetherials, corrupting their essence with promise of power and dominion over Creation.
The Aetherials that chose to follow Lysar on his crusade against the Nine, became Netherials, and forged an antithesis to the Arcanum, a land of constant chaos and destruction – the Nether. Among the Netherials, one stood above all others; Elendarr chose to betray the Nine, wishing to usurp Aila's throne.
For this transgression against Order, Lyria, the radiant daughter of Aila, vowed to brighten the Arcanum as much as she can, and to purge all the that goes against eternal Order. Thus the Sun purged all undead beings that fell into its sight.
Each moon on the Arcane calendar marks another battle in the eternal battle between Order and Chaos. Each force seeking to erase the other. The world stands in an infinite balance of the Two in the Void.