This promo card works in any Fluxx deck, but you might want to make sure that deck has a way to get rid of Creepers...
It says, "If you have this card, you cannot win by meeting the current Goal. However, if another player meets the Goal, you win instead of them. This card moves to the current player whenever a New Rule is played."
This card was originally published in 2009 to help promote the release of Are You The Traitor? in a postcard format with a punch-out card. In 2014 we recreated it as a loose promo card with better quality.