Slytherin organized a party to which they invited absolutely everyone. The difference was that this was not a normal party...it was in the form of a game. The rule was that everyone would come to the party with a mask and a wig. Everyone had to find a partner and get to know each other. At the end of the party, everyone would take off their masks and wigs and reveal who they really were. The only way to know who's standing opposite you before the party is over will be either the person's voice or character. **