- "The corrupted Keepers create the Aether Pyramid, a device capable of absolute power. A schism forms between them and those Keepers untainted by the Dark Aether. War breaks out between the corrupted and uncorrupted Keepers. Facing defeat, the Corrupted Keepers hide the Aether Pyramid on a moon within one of the newly discovered dimensions."
- — Excerpt 1023816121016 of the Kronorium
The Moon Pyramid Device (M.P.D.), or Aether Pyramid, is a pyramid-shaped device created by the then corrupted Keepers. A war broke out between the Keepers and the corrupted Keepers; facing defeat the corrupted Keepers hide the Aether Pyramid on the Moon. The corrupted Keepers were later known as Apothicons.
The pyramid is discovered by Edward Richtofen on January 1940 after he accidentally teleported himself to the Moon as part of the first human teleportation test with Dr. Schuster. Richtofen arrived in the cave where the pyramid was located and touched it. Upon being shocked, Richtofen started hearing many voices of corruption, including that of the Shadowman altering his personality. Richtofen began being obessed with the Aether and Agartha.
Richtofen returned to Group 935 and Schuster a month later with a plan to build a base on the Moon, Griffin Station without telling Dr. Ludvig Maxis. Over the coming months, many scientists started joining Richtofen and worked on Griffin Station. On February 1942, the base is completed and Richtofen revealed Griffin Station was created to study the now called Moon Pyramid Device. Richtofen put Dr. Groph as the lead scientist on the station. The M.P.D. features a circular indented interface at the front made to receive two devices, the Vril Device and the Vril Sphere. On July 1942, Groph and Schuster discovered that the power source of the M.P.D. are souls after killing a rat next to one of the tanks, filling it. From that moment on, Richtofen sent soldiers and scientists to be killed to charge the M.P.D.
Three years later, on October 1945, Groph informed Richtofen the M.P.D. has been powered up and the shields lowered. Richtofen confirmed the launch of Operation Shield and got rid of Maxis and his daughter Samantha by teleporting them away. Unfortunately, Samantha was teleported to the Moon and run inside the M.P.D. where she became corrupted by the Dark Aether. Richtofen ordered Groph to teleport Maxis in the station so he could persuade her to come out of the M.P.D, but Maxis asked her to "kill them all" before killing himself. Enraged, Samantha unleashed the zombies upon the station.
Richtofen managed to survive and went back to Der Riese where he awaken the test subjects he was experimenting upon, "Tank" Dempsey, Nikolai Belinski and Takeo Masaki. They will be known as Ultimis. The four men started a journey across space and time where Richtofen retrieved his journal in the Rising Sun Facility and began to form his plan to defeat Samantha. They activated the Casimir Mechanism in a Soviet cosmodrome, acquired the Vril Device in Siberia, retrieved the Focusing Stone in the Himalayas before returning to the Moon in 2025. Richtofen followed his plan and entered the M.P.D. and took control of the Aether trapping Samantha's soul in his former body.
After freeing Samantha from Agartha in Dimension 63, Richtofen, Dempsey, Nikolai and Takeo, who are known as Primis, were sent to the next destination. Primis eventually reach the Ultimis dimension in 1943 to prevent the future events to unfold. Two years later in 1945, Primis intercepted Ultimis Richtofen in The Giant just after Ultimis Richtofen teleported Maxis and Samantha, leading Primis Richtofen to kill his Ultimis self and trigger fractures across space-time. In one of these fractures, called Deceptio, lead Primis to a Group 935 facility in a castle in Austria to collect Ultimis Dempsey's soul. Primis uncovered the Vril Device and placed it in one of the tomb where a ghostly Keeper rose up. After getting enough souls, the Keeper teleported to Griffin Station and brought the M.P.D. down to the castle. However the Keeper became corrupted by the M.P.D. and Primis had to cleanse it. After the fight, Primis used the M.P.D. to power the Summoning Key, leading to the destruction of Griffin Station and the Moon.
- When shot with any weapon or explosive, it will not show any signs of dents, burnage, or any bullet holes.
- The M.P.D. can be seen on the multiplayer map Remnant from Call of Duty: Black Ops 4.