masseffect

The Geth Colossus is the largest geth ground unit.

Mass Effect

Geth Colossi are similar to Geth Armatures, but much larger with more health, stronger armor and better weaponry. They are distinctive from Armatures because their armor is brighter, somewhat platinum-silver in appearance, with ridges on the back. They are equipped with mass accelerator machine guns and a powerful Siege Pulse mass accelerator cannon. The Colossus is a monumentally dangerous foe, but fortunately they are almost always encountered while in the M35 Mako.

Tactics

Mass Effect 2

There is one Colossus present on Haestrom, which acts as a level boss at the end of the mission to recruit Tali'Zorah vas Neema. A notable trait of this particular Colossus is that it is the Armature steel-gray, not white. Interestingly, the quarian marine Kal'Reegar calls the Colossus an "Armature-class" unit, indicating that at least quarians see it as a variation of the Armature.

There are also multiple Colossi on the Firewalker Pack, but they are fought with the Hammerhead and lack the self-repair mechanism, making them much less challenging.

Capabilities

Offensive

The Colossus possesses a long-range siege pulse weapon and short-range mass accelerator machine guns. It should also be noted that the shots from the Colossus's main gun home in on whatever it is aiming at. This can make the fight very difficult. However, unlike in the original Mass Effect, this siege pulse will not kill in one hit, even on Insanity.

Defensive

The Haestrom Colossus has very strong shielding and armor and will recharge its shields. It is unaffected by Stasis and can continue to target Shepard even while under the effects of Tactical Cloak. It will also ignore any allied geth under the effects of AI Hacking, remaining focused on Shepard's team.

Tactics