When Time Runs Out
If your five-minute timer reaches zero, the Overtime phase begins. The entire dimension plunges into total darkness—you won't be able to see your hand in front of your face without light sources.
Staying Alive in Overtime
Keep glowing lamps or torches in your hotbar before time expires. Light is your only defense against the creatures that hunt more aggressively in darkness. The Chomper specifically targets player-placed lights, so be strategic about where you place them.
Stick with your squad if you have one. Multiple players with light sources can cover more ground and watch each other's backs.
Finding the Exit
Your 
Temporal Compass still works in Overtime, but darkness makes navigation harder. Move deliberately toward the portal location, lighting your path as you go. Avoid breaking the floor unnecessarily—the Chomper will exploit weak spots beneath your feet.
Reach the 
exit portal before monsters overwhelm you. If you die in Overtime, you're trapped in the Backrooms permanently.