Prep-Man
Mr. Atom is a very underrated brick. He's held his own and even harmed PC Captain Marvel and held the weight of the Rock Of Eternity, which was said to be limitless. On top of that, he's a killing machine. Literally.
Is Mongul in TROUBLE?!
http://www.comicvine.com/mr-atom/29-24665/
Is Mongul in TROUBLE?!
http://www.comicvine.com/mr-atom/29-24665/