Lith’s Monster
Solus had no idea what Lith had done, to be exact, either of them did. The creature in front of them wasn't dead nor alive, her mana sense had never perceived anything like that.
A normal core was a mass of pure mana, that could be used to interact with the world energy to give life to spells. Awakened beings seemed to be the only ones capable of using the pure mana to obtain various effects, like Invigoration or spirit magic.
An Abomination's black core, instead, was a stronger but corrupted form of mana, that constantly required massive amounts of world energy just to not dissipate. To do that, Abominations gained unique powers.
The Wither they had faced in the past, had the ability to drain life force even from a distance. The plant thing could split his consciousness to overtake and consume the surrounding vegetation while searching for animal preys.