Why do vampires take aggravated damage?
Aggravated damage is more than mere physical damage. It also rips into what could be called a person’s reality pattern, soul, or spiritual essence. If you were to simply cut off a vampire’s arm, then use a high level Auspex power to view the damage on a spiritual level. You would still see the ghost of the arm still attached to the body. As the vampire regenerates, the flesh flows along the path of the spirit of the arm. If the arm were bitten off by the teeth of a werewolf, the damage would be aggravated. Using the Auspex power would not show you a ghost arm, but a ragged stump. The teeth bite into the spirit of the arm as well as the flesh. Healing requires the spirit of the arm be regenerated before the flesh can use it as a guide. All creatures, especially the supernaturals have a bane, an element which adversely affects them.