I think Gregory only exists in the Ultimate continuity, so i didn't feel the need to specify that in the header. I think this might make a good battle.
Gregory's feats :
1.Literally caught thor's hammer with his bare hands while it was flung directly towards him.
2. Fractured Ultimate Iron Man's helmet, revealing half his face. (again with his bare fists)
3. Broke Captain America's shield using the same hammer he stole from thor
4.Blasted away Tony's chestplate with his...humanoid repulsors.
He has performed all those scenes without even wearing any kind of armor, he literally wore a white tux and that was it. He even proved to be able to shoot energy blasts from nothing but his palms. Clobberin' Time.
Battlefield : male's restroom