Stacking some characters:
The Mummy
The Monkey King - with just the feats from that movie with Jackie Chan, not the generic Monkey King
The Alternate Universe Cop who added the strength of his alternates
The Monk in White Snake - if you haven't watched it, he is a brute. Martial arts, strong telekinesis, lifts a big stone building, agile, that Asian movie leaping - kind of flying leaps, spells.
Are there more to stack and how tough does he end up being?
Certainly a threat to the lower level heroes.