Game: Mass Effect 2 (2010)

Shepard fought Saren the emissary of the first game's Reaper but this time, this dark space entity must be dealt with face-to-face. Although you're assisted by orbiting particle weaponry, gamers felt their pulse quicken as the mechanized beast powered up its one-hit, one-kill death ray. Before meeting this monstrosity, the true face of the galaxy's killers was unknown. What makes this Reaper even more special is the statement (or warning) it delivers to Shepard with its last breath – "the universe is doomed."