User blog comment:PhazonAdictKraid/Superhero Battle: Ultraman vs. Superman - Who would win?/@comment-1733689-20130517023906/@comment-5951231-20130517120725

I envision it more like a Dragonball Z style fight. Ultraman would be too slow to land any hits on Supes in his default giant form so he would shrink to human size. Powers would not be too much of a factor as both combatants have encountered powerful opponents that outclassed them in terms of super powers and come out on top.

Also since Ultraman is powered by light, his attacks could potentially backfire and end up supercharging Superman's powers into overdrive.

On the other hand, Ultraman could alter the frequency of the light he emits to that of a red sun and just wail on him.

If Ultraman's Color Timer went off I would imagine The Man of Steel would help the poor guy up and get him recharged. He is a powerful hero but he's not a murderer. His greatest quality is his compassion towards others. I would imagine Ultraman would do the same for him if he saw a collapsing building and Superman stopped fighting to try and rescue civilians. He would realize that the man he's fighting is a hero and call it off.

Like Phazon said, it could go either way. But in reality, a crossover with these two would me more awesome if they worked together. Superheroes fighting each other has been done to death in comics.