The Ventilation System is perhaps the most critical system to maintain. A functioning ventilation system prevents the appearance of phantom animatronics and ensures clear visibility. If the ventilation system malfunctions (indicated by a red 'X'), you will start experiencing hallucinations (phantom animatronics) more frequently. If the ventilation remains down for too long, your office will begin to black out, making it impossible to see and leaving you completely vulnerable to Springtrap. Rebooting the ventilation system should always be your top priority when it fails. Its integrity directly correlates with your ability to survive the night.
