He's supposedly one of, if not thee, strongest members of the League(s). So, I'm actually curious as to who could beat him. I know he beat Ultraman before, but i'm also wondering if he could do it in the N52.
He could do it in the N52, but his powers are weakened and out of whack right now so he can't properly fight off Ultraman and the rest of the CSA.
Who could beat him in the N52 though? Not sure. There was that one splash of him taking on the entire Justice League so I doubt there are many people who can take him at the moment.