Micheal Korvac (full power) in the DC universe

How big of a threat would Micheal Korvac be if he were to be transported into DC space? Most recently in Iron Man, he defeated the Living Tribunal, and the Inbetweener.

Who would it take to stop him in DC?

The Marvel abstracts are a joke. Having said that, he would wreak havoc on DC Earth till Batman or another prep God comes up with something to stop him.