It's a Dog's Life

The planet Lorella is laid waste, blasted continually by intense radiation, the human survivors digging deep into the planet's crust to escape. Nothing can prepare them though for the birth defects inflicting the new babies born to them. After time, natural selection takes over. The resultant mutations are malformed and twisted beyond the point of recognition as being even distantly related to man.
Now after generations, the dog warriors that rule their own kingdom in the underworld, strive to control the only environment they have ever known. For the beast that has no notion of farming, everything that breathes is their potential dinner, even the lives of their own.