While on a mission in deep space, Brainiac 5 of the Legion of Super-Heroes is captured by Nardo and placed into his Stalag of Space. Nardo was at war with all lawmen in the universe. Lawmen had exiled him from his own world, in a distant galaxy, and so he swore eternal warfare against all who champion the law.
Nardo's race live by having nuclear energy in their veins. He is able to project deadly bolts of force that can incapacitate or kill human beings. His nuclear energy can also cause Durlans to be frozen in whatever shape they were impersonating at the time.
Nardo also has a third eye that acts as a natural radar device and can see invisible forms. It can also project heat vision strong enough to melt lead.