Imposters in Among Us social deduction game can use vents to quickly hide and move between a designated set of rooms, making it easy for them to get away from the room where they left a dead body. Vents can be used as a place to hide from crewmates seeking the impostor. It is also highly recommended for Impostors to close vents afterwords to not attract crewmates' suspicion. But crewmates can see vents opening and closing without seeing who exactly using it from other rooms or outside their circle of vision. That's why this sneaky Yellow Impostor is glimpsing outside and closing the vent so that crewmates would not spot him. A fanart Among Us progress bar for YouTube with Yellow Impostor in a Vent.