2370. Transparent
The healing showed a lot of what needed to be learned about both dark mana and of course about undead mana. Walker could see that the more potent wounds caused from bites and the dark mana being left was very dangerous. The skin and muscle around did not instantly decay.
He could use his mana sense and the knowledge that he gained about healing from others to see that it first caused the muscle to seize up. This caused the muscle to become too tense for blood to flow properly, it also caused bruising in the skin around it. The reaction was also due to the smaller blood vessels beginning to rot. An overall terrifying effect that would have made many healers without proper experience call for a veteran.