10 MORE Star Trek Villains Who Killed The Most
7. V'ger
Another example of accidental, yet highly destructive, power here, V'Ger was encountered by the newly-refitted USS Enterprise in the 2270s. Massive beyond anything that Starfleet had encountered before, it dwarfed not only the ship, and the cloud that surrounded the main structure was said to be greater than Earth's entire orbit around the Sun.
V'Ger had displayed its power by destroying three Klingon K't'inga class vessels, Starfleet Station Epsilon IX, and tragically, Lieutenant Ilia as well. Perhaps destroying may be a little inaccurate though, as all of these were examples of V'Ger downloading, storing, and remembering each of them, instead.
Spock, fascinated by this new encounter, underwent a space walk that took him into the heart of V'Ger's core. There, he discovered the recorded images of thousands of ships, planets, and entire galaxies, all of which it had encountered on its travels.
It is unclear if V'Ger had 'downloaded' these as it had the Klingons and Ilia, though there is no reason to believe that it hadn't. If that is so, then there is little doubt that V'Ger, in its quest to return to its maker, was simply far, far too efficient at its job - and the devastation that it wrought, despite creating a new form of life, is unparalleled in Star Trek history.