Monkey Mode is a game mode which pits virus-infected Monkeys against the crew of Space Station 13. The Human crew must kill the monkeys before they can spread their infection to all of the crew - they must also make sure that no monkeys escape from the station to spread the monkey virus elsewhere. The AI must prevent anyone from leaving the station, human or monkey alike, in addition to helping the human crew as much as it can. The Monkeys must spread their infection to as many crew members as possible, and leave on the shuttle.