Escape Across the Cosmos — Gardner Francis Fox

Falsely accused of depriving the Empire of its dream of a Promised Land by murdering its leader, Kael Carrick was exiled ot the dread planet of Dakkan, a galactic graveyard from which no man returned. But Kael had to return. He alone could dare attempt it. For before his death, the leader had rebuilt Kael's war-ravaged body. A single silicon superman against the advancing terror of the Slarrn World.