"Some supernatural beings are sensitive to it. Also, power is conductive, so having a conductive material in my wards allows the power and ward to connect and complete better." Of course, blood helped too, but that wasn't something you told everyone.
"Not at all. Everyone has to starts somewhere. For example, I have some teas here made of herbs that help with headaches and tension, when brewed the right way. Herbs have been medicine a lot longer than modern medicine has." His voice was gentle as he looked at her. While he realized he was only maybe ten years older than her, he felt oddly fatherly.