Created by Emilio Storme, a brilliant but mentally unstable scientist who was fired from S.T.A.R. Labs. The android was programmed to believe that it was actually a human being that had been given super-powers by his master, Storme.
Storme had sent the android to S.T.A.R. Labs to steal meterological equipment he needed to create a storm-bomb that could devastate entire cities in his quest for world domination. The android was ultimately defeated by Superman.
Thunder was a massive giant who could generate powerful shock waves and could fly.