The Druoda were a Delta Quadrant species capable of building extremely powerful long-range weapons controlled by artificial intelligences, such as the series 5 long-range tactical armor unit.
It's military command was called Strategic Command Matrix.
Until 2372, they were engaged in war with another space-faring species from the Delta Quadrant who maintained a military installation on Salina Prime. (VOY: "Warhead")
This species was only mentioned in dialogue.