A secret Maliwan facility built for developing and testing new weapon platforms.
— In-game description
Midnight's Cairn is a classified Maliwan weapons facility, located on an unknown planet close to the center of the galaxy.
Midnight's Cairn is a top-secret Maliwan blacksite developing powerful new war machines for the company's arsenal. Following the defeat of Maliwan's invasion force at Promethea, Lorelei believes they might regroup and try to attack Atlas again. She contacts the Vault Hunters, asking them to take the fight to Maliwan by raiding Midnight's Cairn and destroying their new robots to prevent them from being deployed.