Harbinger: The main antagonist of Mass Effect 2 and Mass Effect 3 (besides Illusive Man as the secondary antagonist), and leader of the Reaper fleet. It is the largest and oldest Reaper in existence and was the controlling force behind the "Collectors"; who were warped versions of the Protheans.

The Reapers are a fictional fleet of sentient starships that serve as the main antagonists of the Mass Effect trilogy. The design of the Reapers was inspired by H. P. Lovecraft's Cthulhu Mythos deities. Within the series, the Reapers cause galactic-level mass extinctions every fifty-thousand years.

Their main goal is to harvest all organic species and resources in the galaxy for consumption and also to create more Reapers. Once that is complete they remove all traces of their existence and then go back into deep space where they can't be found.

History. The Reapers have existed for at least a billion years, based upon findings on the Leviathan of Dis, an ancient Reaper corpse. Before the Reapers came to be, the galaxy was under the thrall of a race known as Leviathans.