The Stifling Dark is a one-vs-many hidden-movement horror board game with an innovative line-of-sight mechanic for 2-5 players. One player takes the role of the adversary, whose goal is to prevent the other players (the investigators) from escaping through a variety of unique actions. As an investigator, your only goals are to survive and escape. Investigators move around the board in a point-to-point fashion using their base movement speed. They may sprint to move more quickly, but they need to keep an eye on their stamina so they don't become exhausted. Additionally, investigators can pick up and use items, lock and unlock doors, or use their flashlights to try and find the adversary.

Meanwhile, the adversary is secretly moving around the board, trying to stop the investigators from escaping. There are a variety of investigators to choose from, each with their own special abilities. The adversary also has multiple attacks and abilities that change how you play the game. Will you fix the car and drive out, or will you override the gate and try to sneak out? The investigators will need to decide if they want to stick together to watch each other's backs, or split up to race towards the exit. Either way, they must move quickly - the longer the game takes, the more chances the adversary has to stop them! The game ends when either all of the investigators escape (meaning the investigators won) or the adversary achieves their win condition (which is different for each adversary).