Determining who is stronger in mahabharata is more like a cricket match.

Rather than usual powerscaling in other fiction, every dog has his days in this story. Sometimes a character takes on a whole army of warriors alone. Sometimes a weak character wins against a top tier as long as they aren't krishna.

Its becomes less about who is truly the strongest and more about who has the best track record. Or to say who has made more runs. Today karna had a bad performance. Oh don't worry, he will use his fav bat Vijay dhanush and get 6's next day.