Grue, Fire, Water is commonly a two-player game. At the start of each round, each player secretly chooses either grue, fire, or water, and then simultaneously reveals what they have chosen. Grue drinks water, water puts out fire, fire scares grue. The winner of the round is the one who made the more powerful choice. Strip versions of this game are popular - those who lost a round had to remove an item of clothing.

As seen in casinos and gambling halls, professional versions of this game include large machines in order to prevent cheating. The players are divided by a curtain with three buttons on each side. One button has a picture of fire on it, another has a picture of water, and the third bears an image of a gure (shrouded in darkness). Both players pick one. The machine reads the two and indicates a win, a loss, or a tie.