Vir

Vir, or Qxm's Blood, is an inky substance that interacts with, and opens the ability for, arcane magic. All arcana mages use Vir in some way, knowingly or unknowingly, but in large quantities Vir can corrupt an individual's mind or soul.

Vurdmeisters
Vurdmeisters are mages that have fully embraced the power of Vir, and wield it on their body like animated tattoos. The Vir is porous, and bends to their will, so can be used to manipulate their environment, extend the range of spells, or for more brutal, offensive means.

Vurdmeisters have been present in a number of societies throughout Hecaxian history. On Brentia, they have been seen primarily in the nations of Khalivar and Carnifex, though rumours of Aboleth that have managed to gain control of the Vir in such a way on Keldeos have also begun to spring up recently.

Diluvian Oil
Diluvian Oil is Vir that has been wrestled away from Qxm's control by some unknown process. It beats in the heart of every Diluvian, and has retained its corrupting nature. Diluvian Oil is used to convert or "compleat" those conquered by the Diluvian horde, and changes its victims both physically and mentally, until they become unrecognisable as the entities they once were.