E.C. Tubb 
Toyman 
The Dumarest Saga Book 3

Space-wanderer Earl Dumarest is on the planet Toy to consult the giant computer which may contain information on the whereabouts of Earth, his lost home-world.But soon he realises Toy is a place that gives away nothing for free. Before Dumarest can gain the information he needs, he must take part in the Toy Games — must fight like a tin soldier in a vast nursery.And there is nothing playful about the Games on Toy. The pain is real enough; the wounds, the blood — and death.(First published 1969)