M.P.D.

The M.P.D. is a pyramid-shaped device, with a circular indented panel at the front that controls the Zombies. It is what drove Richtofen insane. It uses souls as a power source, as discovered by Schuster when he killed a rat near it. Samantha Maxis was originally suspended within it by accident and used it to send the zombies after Group 935 members, because she wanted revenge for the loss of her father, Dr. Maxis. Following the events of Moon, Richtofen switched souls with Samantha using the Vril Generator, granting him the power to control the zombies in Black Ops II.

Trivia

 * When shot with any weapon or explosive, it will not show any signs of dents, burnage, or any bullet holes.