Every year the Pumpkin King invites us to his castle to celebrate the fall dance in his honor. Castle Party is the craziest party in town and, without a doubt, the most unmissable evening for any monster worth its salt. You can't miss it for the world! The guests are arriving at the castle of the Pumpkin King. As usual, they meet in groups.

It is a "flip and write" game, that is, cards are drawn and written on a board. The active player turns over a card with a polynomial shape, then everyone places a monster card on the table to try and match the shape of the card. Finally, and in correspondence with their own place at the table and their perspective on the shape, the players draw the monsters on their personal boards and try to group the monsters into families to get the best score.

Castle Party has three scoring phases during which players earn points based on how they have organized their guests. When the old cuckoo clock chimes for a terrifying third time. At that point everyone has to say goodbye until next year and leave the party. However, whoever organized the wildest and most fun Castle Party will win a special place in the heart of the Pumpkin King and win the game.