The Dosadi Experiment

Generations of a tormented human-alien people, caged on a toxic planet, are conditioned by constant hunger and war. They are subjects of the Dosadi Experiment, which has succeeded too well. For the Dosadi have bred for vengeance as well as cunning, and they have learned how to pass through the God Wall to exact revenge on the Universe that created them. From the author of the classic Dune series.