Sub-Zero Bag

A Venusian man who would become known as Sub-Zero was a part of an expedition that was launched to establish first contact with Earth. Before the spaceship could enter Earth's atmosphere, it passed through a comet. Everything inside was frozen. One crewman managed to survive, but the exposure turned him into a living ice man that froze everything he touched. He escaped the craft while covered in ice and then made his way to the nearest building. The building happened to be full of scientists experimenting with "gamma radiation." They used the gamma rays to return him to his original humanoid form, though his ability to freeze objects remained.