TRIPLANETARY

Panther SF paperback, 1972. Cover painting by Chris Foss.

"Cosmic Conflict 

In Triplanetary, battle is joined for control of the universe. The Arisians, benevolent humanoids who have declared themselves Guardians of Civilization, war with the Eddorians, shapeless, malevolent beings, hungry for power at any price. They fight on both physical and mental levels, wielding weaponry of inconceivable destructiveness. 

And their battleground is a tiny planet in a remote galaxy; Earth. The swamping of Atlantis, the fall of Rome, the wars that rack the world and blaze through space - all may seem historical accidents to the men involved, but each in reality is a move in a savage universe-wide power struggle... 

Triplanetary is the first volume in the famous Lensman series of novels, an epic saga of galactic adventure on the same magnificent scale as Isaac Asimov's classic FOUNDATION trilogy."