Science fiction writer. His most notable works comprise the 'Berserker' universe, featuring ancient starfaring machines bent on exterminating all life in the universe. These killer robots can arguably be called some of the most evil antagonists in science fiction.
A curious deja-vu feeling of Saberhagen's story "Sign of the Wolf" (see online version at http://www.berserker.com/story-wolfcover.htm ) is had when reading about the "Tunguska Installation":