- "The Keepers seek to exploit the weakness between the dimensions, to allow their master's passage to this world, you must repel their onslaught at all costs!"
- — The Shadowman talking about the Keepers.
The Keepers, also known as the Ancients and the Angels, are mystical creatures in Call of Duty: Black Ops III and Call of Duty: Black Ops 4 that play a major role in the storyline of Zombies. They have appeared in Shadows of Evil, Der Eisendrache as a part of the main Easter Egg, Zetsubou No Shima, and Revelations. They are mentioned in Call of Duty: Black Ops 4 by Richtofen in Blood of the Dead and seen in the Alpha Omega intro, as well as the Tag der Toten outro.
The Keepers are manifestations of the Ancients who were a part of the Order of the Keepers, an ancient order with the purpose of protecting the Summoning Key, and preventing the Apothicons from wrecking havoc upon all dimensions through time and space.
Eons ago there existed only the Keepers, amongst them two individuals who would later be known as Dr. Monty and the Shadowman. However, the corruption from the Dark Aether found its way into their realm and twisted the minds of some of the Keepers. These twisted Keepers resented the other Keepers and waged war on them, becoming the Apothicons. These Apothicons were defeated and those who remained were banished into the Dark Aether forever, afterwards the Keepers ascended to become the guardians of all the dimensions through time and space. As time went on in the Dark Aether the Apothicons were slowly morphed and changed into tentacle like creatures, barely resembling their former Keeper selves. Sometime during the middle ages the Apothicons found a way to reenter creation and attacked the Earth. With the help of the Keepers, the fighting human knights were able to defeat the Apothicons and banish them from their world once more.
In Shadows of Evil they at first try to prevent the characters from handing the Summoning Key to the Shadowman, but later aid them in killing him and retrieving it, but the Key gets stolen by Edward Richtofen. They are shown to be allies of Richtofen and the group in Der Eisendrache, where Richtofen summons one from a tomb using the Vril Generator and aids it in returning to its physical form. In return, the Keeper transports the M.P.D. from the Moon to Der Eisendrache but gets corrupted on the way. After a battle against the corrupted Keeper, the group manages to purge the corruption from the entity. In Zetsubou No Shima, several Keepers attack the player when attempting to pick up the Skull of Nan Sapwe, but get dispatched by the group. In Revelations, Keepers are cursed and the Keeper logo on their chest is now the Apothicon symbol for curse.
In Tag der Toten, when Agartha was banished to the Dark Aether, the remaining uncorrupted Keepers were banished alongside Doctor Monty.
The Keepers appear as some sort of unearthly species of unknown origin. They have large sharp teeth and no visible eyes, similar to the Margwas, and have three clawed fingers on each hand. They don't seem to have legs, but instead levitate. They wear dark red robes with gold embroidery including the Order of the Keepers symbol on their chests. Once in contact with the Dark Aether, the Keepers get corrupted, they turn into a purple color, Apothicon symbols replace the Keepers symbol on their chest, and then they eventually turn into Apothicons like the Margwas and Parasites. Interestingly, Doctor Monty is the only known Keeper to resemble the Apothicons, having a form extremely similar to that of the Shadowman. This is due to his corruption from the Dark Aether.
- In Der Eisendrache in the pyramid room, the pillars surrounding the pyramid are shaped to resemble four Keepers.
- The Keepers have a sword or a dagger on their back.