We have one, the F80
The Tet. It blew up the moon, completely destroyed the Earth, invaded with millions of cloned Tom Cruises and sucked up half the worlds seawater, not to mention create an incredible, gigantic network of extremely maneuverable drones capable of spaceflight. It only died when ten alien power cores coupled with a plutonium nuke was detonated inside it. It also had space-flight capability and learned human architecture, food, language and biology from just one probe sent by humans.
Skynet nuked the Earth and created millions of robots and droneships. That was it. It was destroyed by when someone detonated a couple conventional nuclear cores inside it's base.
To be honest, they're quite similar. But I'd say the Tet would win.