Foil promo card for Locke & Key card game. During the game you can choose to not participate in trying to solve a challenge. If you don't participate, you may draw a Key card instead. Key cards can be played later to alter the rules of a challenge to help you win it or cause other people to lose it. The Harlequin Key Promo card is a Key that is added to the Key deck and can be played as described above.