Silver Key
From Arkham Horror Wiki
Silver Key is a unique item. It first appeared in the Arkham Horror board game.
Card info
Any Phase: Put 1 Stamina token from the bank on Silver Key before making an Evade check to automatically pass it. Discard Silver Key after using it if there are 3 Stamina tokens on it.
Price: $4
Mythos Source
The Silver Key first appears in the story The Silver Key, written by H.P. Lovecraft (1926).
