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The characters are Guile Hero, The Chessmaster, and related. They often engage in a Battle of Wits, Gambit Roulette, or Xanatos Speed Chess.
Weak, but Skilled is often the name of the game here. Note that this can be weak in the normal physical sense, but it can also apply if a character proves Heart Is an Awesome Power by applying a seemingly weak power in incredibly effective or even lethal ways. In Worm's setting full of Persons Of Mass Destruction, for instance, many of The Dreaded are classified as mental-power-based Thinkers. You can fight back against Flying Firepower; Thinkers kill you with Disaster Dominoes they set off last week or leave you sobbing in a corner from a Breaking Speech.
Super-Detailed Fight Narration if the fights are broken down in a way that we see Awesomeness by Analysis in action - say, in a manga Badass Bookworm Alice's thoughts are shown in panel-by-panel thought-box captions as she Curb Stomps a group of enemies, ending with a perfectly calculated catch of the book she threw into the air at the start of the fight, just in time to brain the last opponent with it
In this story, the characters win not by being stronger, but rather by outsmarting their opponents. Basically the fights are very mental.