Unsighted Louver, otherwise known as just Mark, is one of the main tertiary antagonists of the series. He was originally a Cabin Fever Labs drone, being #083 until dying from the Core Collapse, rotting in the mineshafts of Cabin Fever Labs. The AbsoluteProblem encountered his corpse and simply morphed him into a mixture of drones. Even when revived, he still feels MASSIVE amounts of agony from his previous wounds and his new appearance, in general. When hunting, he follows any sounds/vibrations in order to locate and kill his victims by consumption. He is usually silent, but when he does speak, he usually stuttered and has a silent tone.