You are Dust Jacket #
Counter added 11-14-98
From the Back Cover
    Humanity played with fire once too often. It was atomic fire and its ravages produced an almost complete annihilation, but there were survivors. The radiations had not been entirely malevolent in their influence. Genes and chromosomes danced like dervishes in the gamma bombardments, and settled back into fantastic new patterns. God-like beings strode proudly athwart the devastation. Half-human demons lurked in the shadowy ruins. The twilight of humanity faded into a new heroic epoch, behind which the forbidden secrets of the ancient atom gods bided their time. . . .
    Nathkrul had to make an agonising decision. Dare he risk using the forbidden weapons or--must he let the Dark Ones win?
(British, Badger Books SF-85, 1963)