Each round is played with a single deck of 16 cards and 2 large pieces of card (1 red, 1 blue) on which playing cards can be placed. The child will place the cards in the red or blue location depending on their responses.

The top of each two-sided card depicts a character who has a belief or a desire, which the child must reason about using either perceptual information or emotion, or interpreting symbols. For example, the character will be shown to desire a cake more than a cracker by symbolic information on one side (e.g. one thought bubble contains a cake with a thumbs up symbol; the other contains a cracker with a thumbs down symbol); the other side by perceptual information (e.g. she smiles as she approaches the cake and she makes a disgusted face for the cracker). The back of the cards indicate the correct answer with a red or blue circle.

On the bottom of both sides of the card, the character stands between two goal states, one depicted in red and the other in blue; children sort the card by the color of the image that depicts the character's likely goal or action. In successively more challenging decks of the game, children will be presented with characters possessing negative as well as positive desires and goals, with states of ignorance and false belief, as well as states of perception and knowledge. Players are encouraged to talk about mental states and their relations to the agent's intentions and actions as they decipher the symbols on the cards.

The cards will explore desire (denoted by thumbs), thoughts (denoted by thought bubbles), conversation (denoted by speech bubbles), movement (denoted by arrows), perspective (denoted by eyes/obstructions) and emotions (denoted by facial expressions)