Monitors

The Monitors were a race of virtually omnipotent aliens from the DC Universe and were once a threat to the multiverse, though due to changes in the DC multiverse the entire species is extinct save for a single survivor (who is more benevolent than his brethren) - the Monitors are comparable to beings such as the Celestials in Marvel comics and as such were instigators of large-scale events that would reshape the nature of their respective universes.