He deduced that the quantity of blood left in the body after his absorption impacted the power he gained from the sacrifice.
'The amount of undead-creating power I gain from using the Corpse Sacrifice skill seems to be somewhat related to the amount of blood in the sacrificed creature.'
Val's realization was simple but correct nonetheless.
The more blood the corpse has and the stronger it was before its death, the more undead-creating power he could get from casting the Corpse Sacrifice skill on it.
That meant he needed to strike a balance between using his Blood Absorption skill and ensuring that he left enough blood for a valuable sacrifice.
This understanding shed new light on his abilities and presented yet another strategy for Val to ponder.
...
Val continued his journey through the labyrinth.