Players take on the roles of Experts seeking to understand the Alien player, who is seeking to be understood. The Experts will create and transmit 'signals' to the Alien, who has certain rules for how to respond that must be deduced by the Experts. Once the Experts understand these rules, they can ensure that they come to agreement with the Alien, succeeding cooperatively.
On a turn, the Experts arrange black and white pieces on a mat to represent a graphical signal, discussing and debating how and what to send. Once finished, the Alien then replies by using pre-set rules only they can see to add, remove, and adjust the signal, both to be helpful and to try and reach an agreement- represented by a pre-set signal that they are trying to achieve with their limited response capabilities. As the Experts analyze and understand the Alien, they can use limited guesses and a few hint-like abilities to discover what signal they can send that will result in agreement. The Alien even has a little leeway in how they respond- they want to be understood.
After succeeding at the first round, Experts then reset and continue with the same Alien, except new rules are in play on top of the previous ones, showing a deeper and deeper familiarity with the Alien player. After three rounds of successful agreements, all players win cooperatively, and receive a score based on leftover guesses and unused abilities.
