@cmconseils they eventually settle on a silver blade with quicksilver on it, used quickly. It works, but the specific meaning will never be known.

@cmconseils there's an episode of The Unexplored Places where a prophecy about killing a werewolf with "a quicksilver blade" bogs down the party with what that actually means. A silver blade, but quick? A mercury blade, super chilled to be solid? A glass Wesley Snipes filled with mercury, and just sort of thrown at the werewolf?