Legion

"We do not experience fear, but we understand how it affects you."

Legion is a geth that was constructed to operate on its own, separate from the neural network. It marks a "natural evolution" of the geth, who are normally tied to groups in order to maintain sentience, having developed the ability to operate independently and even speak. More specifically, Legion is an advanced "mobile platform" that houses the combined consciousness of 1,183 geth, where as traditional enemy geth only carry one hundred or so. It was designed to integrate with organic life directly, and acts as the voice of the "true geth". It bears a gaping hole in its right chest cavity, the result of being attacked by Alliance security on Eden Prime while searching for Shepard after his death.

Legion is voiced by D.C. Douglas

Geth Infiltrator
Geth Infiltrator is Legion's class power.
 * Rank 1
 * Health: +5.00%
 * Weapon Damage: +6.00%
 * Power Recharge Time: -6.00%
 * Rank 2
 * Health: +10.00%
 * Weapon Damage: +12.00%
 * Power Recharge Time: -12.00%
 * Rank 3
 * Health: +15.00%
 * Weapon Damage: +18.00%
 * Power Recharge Time: -18.00%
 * Rank 4 Unlocks choice between Geth Assassin or Geth Trooper
 * Geth Assassin: Increases weapon damage
 * Health: +15.00%
 * Weapon Damage: +25.00%
 * Power Recharge Time: -25.00%
 * Geth Trooper: Increases health
 * Health: +20.00%
 * Weapon Damage: +18.00%
 * Power Recharge Time: -25.00%

Dossier
Legion was tasked to locate Commander Shepard, it had even recovered a piece of N7 armor found where Commander Shepard had died and it incorporated it onto itself. Shepard must eventually confront Legion to find out why it is hunting Shepard. It is discovered that the geth are at odds with each other and Legion is part of a faction that opposes the Reapers which it calls "the Old Machines" and refers to the ones who follow them as "heretics". Eventually, it joins Shepard's team for the mutual interest of defeating the Reapers and the antagonizing Geth. Tali is understandably at odds with Legion and becomes resentful towards Shepard for recruiting it, resulting in a confrontation if her and Legion's loyalty quests are completed. However, through paragon dialogue options Tali will apologize and remain loyal. Shepard encounters Legion on the derelict Reaper while searching for the IFF required to pass trough the Omega 4 Relay. Legion kills several husks before Shepard finds it attempting to interface with the Reaper's element zero core, at which point it is incapacitated by a husk immediately after opening the door for Shepard.. Shepard brings it back to the Normandy, as intact geth are hard to come by. If Shephard chooses not to sell Legion to Cerberus for research, then after reactivating and speaking with Legion in EDI's core room, Shepard concludes that, as Legion opposes the Reapers, it could be a good addition to the team

Legion can be selected as a tech specialist in the first stage of the attack on the Collectors Base. It is skilled enough that, if the second team has a capable leader, nobody will die. However, otherwise it will panic and the door will jam. While trying to push the door closed, it'll be shot directly in the head by the Collectors, killing it instantly.

Legion's Appearance
Legion presented an opportunity to develop the basic geth design by adding moving parts that allowed it to animate with detailed expressions. Originally added to the concept just for fun, Shepard's N7 armor became an integral part of Legion's appearance and back story. A large hole is visible in Legion's torso - a wound sustained from gunfire while it was Eden Prime searching for information related to Shepherd.

If questioned, Legion reveals that it found the armor while retracing Shepherd's steps and ultimately used it to repair damage the damage it sustained. However, if pressed why it specifically chose to use Shepherd's armor above all else Legion will become evasive and quietly state "no data available".

Loyalty
After obtaining Legion, you can get the coordinates to a "heretic" station. Go to the geth station and complete the quest to gain Legion's loyalty and his Geth Shield Boost ability.

Trivia

 * Legion's name is given to it by EDI who suggests the biblical passage "My name is Legion: for we are many". Legion acknowledges it is a fitting metaphor, as it describes itself as a geth terminal or representative.
 * Legion was the first character seen in any Mass Effect 2 media, appearing in the teaser trailer.
 * Should you bring Legion to the Migrant Fleet in order to assist Tali's trial the quarian guards will point their guns at it. Through dialogue Shepard can either convince them to allow Legion to stay on the ship or be forced to send it back to Normandy.
 * Having Legion in your party when assisting the stranded 'geth agent' asari on Citadel creates amusing dialogue between the C-Sec Customs Officer and Legion. When the Officer explains the new security protocols against geth infiltration, Legion responds by stating 'Geth do not infiltrate'. The Officer refers to Legion as a 'personal synthetic assistant' and suggests Shepard to leave it at home, to which Legion retorts 'Geth do not intentionally infiltrate'.
 * If you wait long enough in the AI core Legion will do the Robot.
 * As a result of its artificial intelligence Legion speaks in a simple fashion, and when it does, its word structure is very organized.
 * Legion regards itself not as a single being, but as an AI platform, and sometimes refers to itself as "we". Though it is arguable that technically by acting through the neural Network that connect all Geth they act as "One".