Sprite

Similar to tailed beasts in Naruto. Sprites were created by Gaia and Thaumus, the two children of Achelous. Achelous had originally made the Alpha-sprite, an all-powerful incarnation of his will designed to shape Marn in his image even if he perished. He did so with good intent, but he was corrupted by unknown chaotic energies and Alpha-Sprite was twisted as well. After Achelous died, Gaia and Thaumus separated Alpha-sprite into separate entities: The Sprites.

There are only 11 unique Sprites in the world, most of which reside in Yatan. Each Sprite was a life created by Gaia, and imbued with a fraction of Alpha-sprite's power. In doing so, Alpha-sprite was destroyed and distributed among the 11 Sprites. Gaia scattered the Sprites around Marn and entrusted them with individuals she believed could keep them apart. Alpha-sprite has never been revived since his destruction.

Somnium, an incarnation of another watcher, wishes to combine the Sprites to create Alpha-sprite to bring forth his creator. The combined powers are the only feasible thing of bringing such a might life back from the dead. He has possession of only one Sprite, and Gamma guards two, and Kenlow possesses one, leaving the rest have yet to be discovered.

Sprites are NOT Sources. Sources can be thought of as fragments of a fallen Watcher. But more correctly, Sources are the energies that make up all Kandalorians and are recycled to newborns. Each Source is a living entity, similar to Sprites, but do not have nearly as much power.