Wolfsbane

Wolfsbane, from Eng. "wolf" + "bane", a of the Ancient Greek term λυκοκτόνον (lukoktónon, from λύκος lúkos, "wolf" + κτείνω kteínō, "I kill"), appeared in. It is a plant that is rubbed on a person's skin or clothing in order to prevent a Blutbad from detecting their scent. Blutbaden know about Wolfsbane as a way for others to disguise themselves, but if it is not applied correctly or thoroughly enough, their sense of smell is strong enough to still detect one's scent.

Trivia

 * Wolfsbane is actually based upon the flowering plant in the genus, which is also known as wolf's bane, among several other names. These flowering plants got the moniker wolf's bane because the extracted toxin was historically used to kill wolves.