These motion detector droids will continuously scan various hallways around the Military Training Facility and the Antarctic Transport Terminal. If you happen to get detected, expect a Hunter or a Sweeper to appear within seconds to attack you. If you do get detected, the creature that spawns will remain in this location until you kill it. But if you do kill it, the Spotter will reactivate and start scanning again next time you enter the location.
Sometimes Spotters will disappear and reappear during certain conditions, such as when you have acquired a key item or performed a certain action.
Jet Hangar Corridor - Military Training Facility B1
2 Spotters - Appear here when you are playing as Chris, and after acquiring the Door Knob. They will disappear once you have acquired the Turn Table Key.
1 Spotter - Appears here when you are playing as Chris, and after acquiring the Door Knob. It will disappear once you have placed the Tank Object on the diorama in the Diorama Room.
1 Spotter - Appears here when you are playing as Chris, and after acquiring the Door Knob. It will disappear once you have acquired the Turn Table Key.
Jet Hangar Corridor - Military Training Facility B1
2 Spotters - Reappear here when you are playing as Chris, and after you have acquired all three proofs from the Airport. They will disappear once you have acquired the Eagle Plate.
1 Spotter - Reappears here when you are playing as Chris, and after you have acquired all three proofs from the Airport and inserted at least one of them into control panel inside the Diorama Room. It will disappear once you have acquired the Eagle Plate.
2 Spotters - Appear here when you are playing as Chris. They will temporarily disappear once you have explored the Main Hall for the first time, but will reappear whilst you have the power switched on within the High Voltage Room. They will also reappear if you have to fetch the Serum to cure Claire. They will disappear permanently once you have fully revived Claire in the Main Hall.