Wolfs bane: Like Vervain to vampires, witches needed a way to defend them selves against werewolves. They do this with the herb aconite or monkshood, More commonly known as wolfs bane. It is an potent herb and a werewolf's most well-known weakness. If a werewolf makes physical contact with wolfs bane in any form, it will burn and weaken them. These affects extend to hybrids as well, who are vulnerable to both wolfs bane and Vervain as a result of their dual nature.