Suggested by Sonic Solomon Grundy may not be one of my favorite DC villains but the guy does pack a real punch. When he returned in his zombie mode even Superman was having a hard time against him. I have no doubt that Mr Mxy would also be running at the end of his rope here. He has a lot of reality warping skills and some energy blasts but nothing that would really hurt this zombie. Try as he might, there’s no way for Mxy to stop him. Solomon Grundy wins.
Depending on what form Grundy has, I think he loses this. Most of the time, he functions as powerful but dumb muscle for any supervillain team or fight. You need more wit to outfox Mxyzptlk.
True, Grundy’s not always the smartest of villains. It’ll be difficult for Mxyzptlk to really deal any damage though. Grundy’s durability is really insane