Puck is severely allergic for silver, it burns her skin and it's the only metal (and way) that can slow or stop a Werewolf from regenerating their wound(s). Werewolves are known for their rapid recovery during battles. When they're in their berserker mode, they're at their peak strength and are immune to any pain inflicted to them. Their regeneration triples in this short time window. However, with silver, one can stop the regeneration process to slow them down. There's no silver on planet Basil. In fact, smuggling silver is a severe crime, and the punishment is usually death by being burned alive. By wearing silver, it's a direct attack against the native population. The silver will be confiscated and destroyed. The punishment for wearing silver is a case by case thing. Werewolves usually can smell silver and it makes them nauseous. Puck takes medication to help her deal with the nausea as silver is a very popular metal on planet Earth.
