"Betrayal at House on the Hill" is a cooperative board game where players explore a haunted mansion. Each player takes on a unique character, each with special abilities, and they work together to uncover rooms and collect items. The game features a modular board that changes with each playthrough, creating a different experience every time. As the game progresses, one player will trigger a "haunt," turning them into the traitor. This player then works against the others, who must collaborate to complete objectives and escape the mansion. The game combines strategy, exploration, and surprise, making it a popular choice for fans of horror and mystery.