The Excavator is a giant mining machine. They are bucket-wheel excavators. They feature as interactive obstacles in the Zombies map Moon on Call of Duty: Black Ops, in addition to making background appearances in the campaign level "Vorkuta" and the multiplayer map, Radiation. They also make background appearances in Call of Duty: Modern Warfare 2 and in the mission "Down the Rabbit Hole" and Special Ops mission Black Ice in Call of Duty: Modern Warfare 3. In Call of Duty: Ghosts the multiplayer map Behemoth is set on a giant excavator.
Three excavators appear in Moon: Pi, Epsilon and Omicron, each with their own control panel in the starting room. Periodically after turning the power on, a warning will play out in the beginning of a round telling that an excavator is about to breach an area of the station. The player will have four minutes (with rapid subsequent warnings in between) to use the Hacker on the panels in the starting room that control the excavators. The excavator can be seen slowly advancing towards the station, and if the correct panel (which glows green) is not hacked in time, it will breach into its assigned area, removing all oxygen and artificial gravity in that part of the map. The terminal can still be hacked afterwards, though oxygen and gravity will not be restored. Of the three excavator terminals in the spawn room, only Omicron is on the left side. Pi and Epsilon are together on the right side of the spawn room. All three terminals are very close to doors, making them easier to hack without oxygen in the spawn room.
The excavator can kill players as well if they come into contact with it. When the wheel is descending on the spot, it will kill any players without Juggernog immediately, though players with Juggernog can withstand the damage for a short time (similar to electric traps in earlier maps). When killed this way, the player cannot be revived and they will spawn next round. The player can also be downed by running into the wheel when it is already down, though this time the players can be revived.
Each excavator is assigned to a specific area:
- Excavator Pi will breach tunnel 6, blocking off the door closest to the power room and making it impossible to buy an M16 or ammo for it
- Excavator Omicron will breach tunnel 11, blocking off the second door from starting room and making it impossible to buy a PM63 or ammo for it
- Excavator Epsilon will breach the biodome, making the Gravity Lifts less hazardous as the player can no longer receive fall damage due to low gravity
One Giant Leap (5 / Bronze Trophy ) - In Moon, become trapped in the Receiving Area and free yourself through resurrection in co-op. (Requires Excavators Pi and Omicron to be blocking off the Receiving/Starting Area from the rest of the map and activates the Easter Egg song Nightmare .)
Ground Control (10 / Bronze Trophy ) - In Moon, prevent each excavator from breaching the base in one game.
- The stands the control panels are on have symbols for each excavator, an ε, O, and π. The ε is mistakenly placed on the stand for Omicron, and the O is misplaced on Epsilon's.