Vigil

Vigil is the V.I. left to monitor the scientists of a long abandoned Prothean research facility. His holographic interface had been badly damaged but his memory core was still fully functional. His personality had been imprinted with that of the Chief Prothean Overseer of the IIos, Ksad Ishan.

After guiding Shepard to its chambers by using force fields, Vigil informs Shepard of the fate of the Protheans in hopes of preventing the same end coming to the current inhabitants of the galaxy. It explains that the Reapers destroyed the Protheans, following a destructive cycle that had gone on for millions of years. The facility of Ilos, however, was saved because records of the station were destroyed in the Reapers' initial attack. Seizing the opportunity, the staff of the facility entered cyrosleep while Vigil looked after them until the Reapers had retreated.

The Reapers' attack lasted for centuries and as time went on, Vigil was forced to shut down stasis pods in order to maintain power beginning with non-vital personnel, eventually ending up with only twelve scientists alive centuries later when the Reapers' finally disappeared. Knowing their numbers were too few to repopulate, the scientists instead set out to prevent the same fate befalling future species. They made use of the Conduit to travel to the Citadel and disrupt the Keepers from sending out the signal that allowed it to function as a mass relay.

Vigil then gives Shepard a data file that will grant him control of all the Citadel's systems in order to prevent more Reapers from coming.

Vigil was voiced by David Shaughnessy.