'This exclusive, limited pack includes new Halloween-themed contents to be played with King of Tokyo! Meet Pumpkin Jack and Boogey Woogey! These scary new monsters come with their own sets of Evolution cards. This mechanic introduced by the Power Up! expansion provides each monster with 8 square-shaped cards to mutate into an even more nightmarish version of itself! But for Halloween, the original King of Tokyo monsters may want to look a bit spooky too: 12 new Power cards allow them to fit in at any party! Costumes, a brand new type of card, have powerful and fun new effects, but can be stolen from your monster any time someone rolls 3 claws.' Halloween is an expansion of King of Tokyo. You need King of Tokyo to play it.