Legion is the name taken by the gestalt consciousness formed by 1,183 geth programs inhabiting a unique geth "mobile platform". Legion is a independent individual and as of now, doing their job alone.
Legion is a unique geth mobile platform, designed to operate outside the Perseus Veil and interact with organics. To that purpose, it houses 1,183 geth programs, as opposed to the roughly one hundred found in other platforms, enabling it to operate independently and speak. In order to facilitate communication with organics, Legion possesses several panels on its "head" that move to simulate facial expressions. These flaps serve the same purpose as eyebrows in organics, raising to imply surprise or interest and folding forward (much like the furrowing of the brow) to show concentration.