The World That Death Made — Lloyd Biggle Jr.

"First came pounding pain: blunt strokes of a relentless bludgeon that slowly ground Caland's brain cells to a pasty slime. When finally the brutal throbbing diminished, a searing rapier of blinding pain probed with fiery slashes, isolating, cauterizing each quivering nerve. His body twisted and turned, tensing with each scalding incision..." Jarv Caland is told by the Polytechnic Institute that he had been killed--his skull crushed--in an accident. He'd been brought back to life by the Institute's renowned research team, his brain rebuilt with metal and wires and...who knows what else. This doesn't explain, though, why Caland is being transported around the galaxy to strange worlds, where he wakes up not remembering how he got there--or who he is--or why he's there. Death and destruction follow in his path: earthquakes, tidal waves, and volcanic eruptions of unprecedented size. And then he arrives on the world called Mort--death--where he must corner the demons that are haunting him, and finally face the puppet-masters who control his every move. A first-rate science fiction puzzle by a master storyteller!