A game of outrageous bluffing, honest haggling, and crafty negotiation. It's Halloween! Time to don your scariest costume and run through the neighborhood shouting "Trick or Treat!". Collect costume and treat cards, and you're on your way to winning Halloween Party. But beware--your opponents may play tricks on you!

Simple enough. But is it? Halloween Party has a ghoulish Twist--You can't play your own cards! You must trade with your opponents, playing the cards they give you, and letting them play your cards. Can you trust them to trade the cards you want? Probably not. But that's where the fun begins.