The Radioactive Civilization was actually the winner of the previous Battle of Divine Will. And as you probably all guessed, the people who ventured into the ruins brought nuclear devices with them and got irradiated.

This civilization from a distant past was extremely brutal and cruel, and one of the people they preyed on got exterminated by billions (well, they were part of the 4 races fighting the Battle of Divine Will then), and their victor particularly fancied torturing them with radioactivity. Their dried up corpses are littering the entire underground of the southern desert peninsula where the Sand People (Echo and Lorgar’s compatriots) currently live, and have noow produced oil !

Their dessicated bodies have a piezoelectric effect and will be used as material for tracer bullets after a catastrophic night ambush led by the Senior Demon Ursrook on the railway works to Taqila (I’m using the novel’s spelling here), because the heavy machinegunners were unable to see where they were shooting to in the dark… :p