Space Station 13

Space Station 13 is an open-source multiplayer video game that runs on the BYOND game engine. Players take the role of crew members on a spaceship. Different players have different roles, including the ship's captain, security officers, scientists, engineers, and doctors, as well as more novel jobs like bartender and clown. However, each round, there is also at least one player taking an antagonistic role, such as a traitor, shapeshifter, or nuclear saboteur. Regardless, players are generally expected to role-play, fulfilling the role of whatever their job is. The goal of the game for the antagonist(s) is to accomplish their goals by subverting the station and avoiding detection, while the other players' goal is to weed out the antagonists and prevent them from executing their objectives.

Space Station 13 is a game noted for its depth and complexity, and the resulting chaos that can result from all players trying successfully or unsuccessfully to fulfill their roles. This is compounded by the game being open-source, which has led to a number of different groups each hosting their own servers with varied rules and gameplay mechanics.