2 Étoiles sont nées is a 3D cooperative adventure game in which two children explore worlds shaped by emotions while searching for their missing parents. Each world introduces its own rules, puzzles and environmental constraints, requiring the characters to cooperate and understand how that emotion affects the world. Players can reverse gravity through the Inverted State, allowing them to walk on ceilings while transforming environmental elements, hazards, accessible paths, gameplay rules and music. The game can be played in local cooperative multiplayer or solo with an AI-controlled companion.