Atlas
Cerberus Heavy Combat Mech
The Atlas was a large piloted combat mech fielded by Cerberus during the Reaper War. Heavily armed and armored, it was developed as a larger and more powerful successor to the YMIR mech and carried a living operator inside an armored canopy.
The Atlas was a large piloted combat mech fielded by Cerberus during the Reaper War. Where earlier walkers operated without a crew, the Atlas was built around a living operator, seated in an armored canopy, directing a heavily armed and armored machine into battle. It became one of the most formidable ground units in the Cerberus arsenal and was later adopted by the CAT6 mercenary company as well. (Mass Effect 3; Mass Effect 3: Citadel)
Design and armament#
The Atlas was a slow but imposing machine, a large target that nonetheless concentrated heavy firepower in a single chassis. It was equipped with a rocket launcher whose guided missiles were difficult to evade and which left a lingering burn on whatever they struck, and with a high-powered mass accelerator cannon for sustained fire. At close range it relied on a heavy claw arm, which it could swing, slam into the ground, or use to seize and crush an opponent outright. (Mass Effect 3)
For defense the Atlas carried durable kinetic barriers backed by armored plating across its shoulders, knees, and lower body, and it could fire smoke grenades to screen its advance. The operator sat within a reinforced canopy at the front of the machine; if the canopy was shattered the pilot was left exposed, and a captured or abandoned Atlas could be commandeered and turned against its former owners. When destroyed, an Atlas was consumed in a violent explosion powerful enough to threaten anything nearby. (Mass Effect 3)
Service#
Behind the scenes, BioWare's official art book records that the Atlas was first conceived as a heavier version of the automated YMIR mech with a soldier inside. A protective canopy was then added, and the frame was enlarged until the Atlas stood considerably larger than the YMIR. (The Art of the Mass Effect Universe)
Cerberus fielded the Atlas throughout its campaigns during the Reaper War, deploying it as a heavy unit that could absorb fire, protect lighter troops, and grind down defended positions through sheer firepower and durability. The CAT6 mercenary outfit fielded Atlas units of its own, functionally identical to the Cerberus models but finished in a distinct gray camouflage. A destroyed Atlas marked with the emblem of the Talons was also recorded, evidence that the machines saw use beyond Cerberus lines. (Mass Effect 3; Mass Effect 3: Citadel; Mass Effect 3: Omega)
Frequently asked questions
- What was the Atlas in Mass Effect?
- The Atlas was a large piloted combat mech used by the pro-human organization Cerberus during the Reaper War. Unlike the automated YMIR mech, it was crewed by a living operator who sat protected within an armored canopy.
- How was the Atlas armed?
- The Atlas carried a powerful rocket launcher that fired guided missiles, a high-powered mass accelerator cannon, and a heavy claw arm for close-quarters fighting. It was protected by durable shields and armored plating and could lay smoke to cover its advance.
- Who used the Atlas?
- Cerberus deployed the Atlas widely during its campaigns, and the CAT6 mercenary outfit also fielded units of its own, marked in a distinct gray pattern. An image of a destroyed Atlas bearing the emblem of the mercenary group known as the Talons was also recorded.
Sources
- GameMass Effect 3, BioWare, 2012
- GameMass Effect 3: Omega, BioWare, 2012
- GameMass Effect 3: Citadel, BioWare, 2013
- BookThe Art of the Mass Effect Universe, Dark Horse Books, 2012 (official art book)
Spotted a factual error or a primary source we missed? Email a correction. Every flagged claim gets reviewed.
Followed from this entry

Cerberus
Cerberus was a clandestine, human-supremacist paramilitary organization led by the Illusive Man, willing to use any means to advance humanity's place in the galaxy. Branded a terrorist group by both the Systems Alliance and the Citadel Council, it was ultimately destroyed during the Reaper War.
Reaper War
The Reaper War was the galaxy-wide conflict that began in 2186 when the Reapers emerged from dark space to harvest all advanced organic life. It saw the fall of Earth, Palaven, and Thessia, the forging of unlikely alliances, and a final battle over Earth that decided the fate of every species.
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M-25 Hornet: the Cerberus burst-fire submachine gun
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Phantom
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Mentioned in2 entries
Dragoon: Cerberus's biotic shock trooper
The Dragoon was a heavily armored Cerberus combat specialist of the Reaper War, a biotic shock trooper who lunged across battlefields behind whips of yellow biotic energy. Often linked by players to Project Phoenix, Dragoons shunned cover, hunted in pairs and trios, and finished fallen enemies with a stomp.
Krysae Sniper Rifle: Turian Anti-Reaper Weapon
The Krysae was a turian antimateriel rifle rebuilt to kill Reaper creatures, firing armor piercing explosive rounds with proximity fuses that burst over cover and shredded massed enemies. In a desperate wartime move, the turians released its full specifications over the extranet so that nearly anyone with a fabricator could build one.
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