Mr Freeze

With the Nolan Batman films, we've seen a very realistic universe in the portrayal of Batman's main gallery of rogues, as well as the technology, and the world in general. So far, we've seen all of Batman's villains maintain a foot in reality and a foot in comic book fantasy. For example, Two Face did not go from the White Knight of Gotham to a full blown crime lord that lived by steeling in the way he did in the animated series. He would have inevitably died of an infection had he continued to go about Gotham City on an endless pursuit of revenge, so in the movie, The Dark Knight, his rampage only lasts one day.

Another example is Raaz Algule. He is not literally immortal as he was in the animated series or the comic, he was instead only metaphorically immortal (as far as we've been told at least). The rest of Batman's villains in the Nolan films thus far have not really required any great suspension of disbelief for their characteristic "powers" to be seen. Like the Joker's slicing of people's faces and use of explosives rather than the toxic joker poison that causes people to have facial and respiratory spasm causing them to grin and laugh and Scare Crow's use of an organic hallucinogen to induce fear.

This is my idea for a Mr Freeze to be used in a Nolan Batman universe. Victor Freeze is working on a means of cryogenic semi-hibernation in humans in order to prolong the life of his wife who is suffering from a rare disease for which there is no cure. He is working for a rival company to Wayne Enterprises, Gothcorp, on powered exoskeletons for the military and various ways of refrigerating systems without compressors. A type of microwave emitter that activates a chemical catalyst to rapidly absorb heat energy and reflect it back through a different microwave frequency. The Gothcorp president finds out that Victor Frieze is avoiding development of the exoskeletons and is using company property to try to keep his wife alive. The president tries to blackmail Victor to develop the exoskeleton or he will take his wife off life support. Frieze trying to plead with the president to allow him to complete his work on the hibernation technology gets in a fight that causes a malfunction in the equipment. Frieze falls into the hibernation pod keeping his wife's condition from deteriorating in order to shield her body from the radiation of the malfunctioning equipment. There is an explosion and both Frieze and his wife's body are not found.

Several months later, Mr Frieze wearing a powered exoskeleton which has to keep his body at sub zero temperatures in order for him to survive is using a miniaturized version of the microwave refrigeration technology to destroy Gothcorp's industrial parks and property. The cold gun mixes the catalytic gel with water in a stream spiraling around the microwave beam. This causes the water to almost instantly freeze solid and destroy anything it has soaked into. He carries a large cannister of water on his back.

Batman attempts to stop Frieze but is outmatched in strength as Frieze's suit amplifies his strength enormously. Frieze's weapon is also extremely deadly as it can causes skin to instantly freeze solid, luckily his armor protects his skin from the effects of the gun but is also destroyed.

You could also play around with the conflict of interest considering Gothcorp is a competing company to Wayne enterprises and Bruce Wayne knows the CEO is corrupt.

Frieze is consumed by revenge in the same way Harvey Dent was, except Frieze's wife is still alive. You can also play around with Frieze's obsession with trying to cheat death for his wife and tie it together with Bruce Wayne trying to let go of the death of Rachael Dawes and his parents. Potentially, you could have another character associated to Bruce who suffers from the same disease as Nora Frieze, like maybe Alfred Pennywise or Lucius Fox. (Joel Schumakker gave Alfred the same disease as Nora in Batman Forever.)

This idea for the sequel may perhaps tie into the movie adaptation of Batman Beyond since Victor Frieze's powered exoskeleton might be adapted for use by Terry McGinnis as the new Batman. Or perhaps Bruce Wayne might incorporate aspects of the powered exoskeleton in a new suit for himself.