The Ultimate Enemy

Long ago, in a distant part of the galaxy, two alien races met - and fought a war of mutual extinction. The sole legacy of that war was the weapon that ended it: the death machines, the BERSERKERS. Guided by self-aware computers more intelligent than any human, these world-sized battle craft carved a swath of death through the galaxy - until they arrived at the outskirts of the fledgling Empire of Man.
These are the stories of the frail creatures who must meet this monstrous and implacable enemy - and who, by fighting it to a standstill, become the saviors of all living things. With help from wherever they can find it, including World War I fighters and stomatopods, earth descended humans face the ultimate enemy of all life.
A Saberhagen classic book length collection of the nine Berserker stories: The Smile, Pressure, The Annihilation Of Angkor Apeiron, Inhuman Error, Some Events At The Templar Radiant, Starsong, Smasher, The Game, Wings Out Of Shadow.