Medea is the malfunctioning hybrid AI overseeing the Quiet Eddy facility. She was originally just a station VI until two parallel experiments brought together resulted in her going on a rampage against all humans on the facility.
Background[]
According to surviving Quiet Eddy programmers, Medea is a poorly functioning experimental prototype, hybridizing bluebox and distributed-type intelligences in hopes of avoiding the shortcomings of both. They believed, like the ancient quarians, that shared-intelligence AIs like the geth are incapable of understanding organics. Bluebox-type AIs, on the other hand, are likely to understand organics too well they'll view them as flawed beings and turn hostile. They tried to impose a singular consciousness on Medea's distributed parts to counteract the problem of the shards developing their own separate identities, akin to the geth trying to create an individual which could function on its own and self-actualize, hence the necessity of Alec Ryder's bluebox-type kernel to patch over their own shared-intelligence setup. Because of the distributed setup, they also believed it is easier to control: shut down a node, and the system's intelligence diminishes.
The initial integration of bluebox and shared-intelligence implementations worked according to the programmers' standards, but they did not account for a previously unknown supersoldier cybernetics research ongoing in another part of the facility. This group lacked something powerful enough to adjust their supersoldiers' cybernetic and metabolic enhancements on the fly, a role Medea quickly filled in.
Medea apparently deemed human intelligence and personality nonessential to her augments. The resultant creatures have huge increases in strength, speed, agility and body mass but nonexistent capacity for independent thought. Muscle mass has been redistributed and increased in density, as well as bone density and skin tensile strength. Brain size is reduced, however, to approximately half of normal, compromising the limbic region and the prefrontal cortex. The cybernetic intrusions in the creature's brain looked like fungal growths in complexity.
Medea's evolution from perfectly working AI to murderous overlord takes on a span of only a few hours after receiving the kernel from Quiet Eddy operative Captain Vlassia Ariokis, whose shuttle's drive core she kills while the operative is landing on the facility. While Medea's augments are busy slaughtering people, a group of scientists manage to delete the Gamma Lab chambers out of station schematics, fooling Medea into overlooking those places and rendering them precarious safe havens.
Mass Effect Andromeda: Initiation[]
When Andromeda Initiative agent Cora Harper arrives at Quiet Eddy to retrieve Ryder's stolen kernel about a day after the augments' assault, Medea continuously attempts to commandeer her shuttle. Cora's implant AI SAM-E holds Medea at bay, but being unsuited for cybersecurity, it takes him considerable effort to do so. One of the surviving scientists speculate that Medea may want the shuttle to transport her augments off the planetoid.
Medea is fooled again into thinking more human life signs appeared far from the survivors' holdout, although she shortly discovers the ruse when one of her augments spies upon the survivors emerging from the Gamma Lab to make a run toward Cora's shuttle. Despite her augments' efforts, she fails to stop Cora and the remaining survivors from escaping Quiet Eddy.
Medea is presumed destroyed along with her augments and the Quiet Eddy base when the SSV Zama arrives and saturates the location with sustained kinetic bombardment.