Cat in the Box is an extraordinary trick-taking game centered around quantum mechanics and cats. Similar to the famous thought experiment by Schrödinger, the cats on the cards only assume their final state or color when played. At the beginning of each round, players bet on how many tricks they can win with their hand cards. Then, each person takes turns playing one card – whoever plays the highest card of the led suit or the trump color red wins the trick. However, the color of the hand card is only determined at the moment it is played. If a player cannot or does not want to follow the announced color, they must change the color but cannot play the originally required color for the rest of the round – in a figurative sense, they no longer have any cards of that color in hand. Each color-number combination may only be played once throughout the game. This is indicated on a small game board, where the player marks the corresponding field with a marker of their color. The game ends when all hand cards have been played or when a player finds themselves unable to play any of their cards. Points are awarded for the number of tricks won. Additionally, connected fields on the game board marked with their own markers grant extra points, but only if the predicted number of tricks has been achieved.