Harbinger

Harbinger is the main villain of Mass Effect 2. He is a Reaper, like Sovereign from the first game, and is the controlling force behind the evil aliens known as the Collectors. He directly controls the Collector General, and during gameplay he can possess the body of any regular Collector making it into a boss unit. Harbinger also expresses an interest in possessing Commander Shepard's body once he's been killed.

Harbinger's goal is to use the Collectors to kidnap humans and use them to create a humanoid Reaper robot. At the end of the game, Shepard and friends destroy this Human-Reaper and blow up the Collector's base. Harbinger is then forced to lead the Reaper invasion manually by slowly traveling across the Galaxy towards civilization.

Harbinger is best known by fans for his famous line "ASSUMING DIRECT CONTROL."