Anti-mana

Anti-mana was an I.C.E. Age concept reintroduced by the Vvrael Saga. In the Shadow World cosmology, Essaence was the foundation of all Existence, which ran between poles of Order and Chaos. Material "planes of existence" were lowly ordered, whereas the chaotic realms were the home of demons and the dark gods. At the very furthest extreme was The Unlife, the "heart of Chaos", which was pure Anti-Essaence and so inherently destructive of all existence. While there were also Outer Planes that were not part of Existence, such as the Pales and the Black Hel, the "near" ones only resembled our own due to accidental parallels with the axis of Chaos.

The Dark Gods were originally "manifestations of the chaotic aspects of the Anti-Essaence", prior to the introduction of the Arkati concept for the modern history. (The Liabo Gods had been stranded here from a higher plane of existence, as a result of a cataclysm which allowed magic to exist in our world, which were generally inaccessible from lower ordered realities.) With the introduction of "anti-mana" as a power for creating the undead, and the Dark Gods now being considered the same race and nature as the Liabo pantheon, the unholy nature of undeath and the precedent of extra-planar entities causing their existence was much more ambiguously defined.

Anti-mana typically takes the form of tendrils or voids, due to the sentient nature of the Vvrael in The Rift. In the I.C.E. Age form of the concept, it was supposed to be so alien to our own existence, the most powerful mages would only be able to detect it as an absence in the background radiation that surrounded all things. Whatever dark magics used it would seem to be another source of power entirely.