As a concept, the One Punch Man is fascinating but he's kind of a 1-trick pony. Also, no matter how hardcore he is, there's just some situations that 1 punch doesn't do it.
Like the Hulk, who gets increasingly more powerful the more his adrenaline goes up. His literal "Madder Hulk gets, stronger Hulk gets" means his strength and endurance increases geometrically with his rage, plus he heals faster too.
This is the most realistic depiction of them fighting I've seen yet.
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