The villain attacks, the hero dodges--rinse and repeat.
A leading theme in a LOT of battles, because it shows off: 1) the villain is stronger and could Really Hurt the hero if the hero misses one step, 2) it stretches out the fight longer, and 3) the hero is smarter and more skilled, and way cooler to be even if he's always one step away from getting pulped. Usually ends when the hero finds a reason to attack back and/or discovers how to hit harder, if he wasn't just using Deadly Dodging all along.
(Elements of this also appear in horror/suspense and other grimmer scenes, where the hero *barely* stays ahead of the villain and probably just wants a chance to run for his life.)
Basically deconstructing Plot Armor into a whole lot of specific moves so that each of them "just might go wrong after all." (May be combined with Imperial Stormtrooper Marksmanship Academy if there are enough ranged attacks on the villain's side.) Tactic of choice for the Fragile Speedster but frequently required for any hero type except the Mighty Glacier (who temporarily becomes Faster Than They Look the moment the villain finds an attack that really works on him); even Superman does a lot of dodging when the enemy's Got A Bigger Gun. Related to Flynnery in that both try to build the hero's coolness out of how he can duck around like a hyperactive flea and make it work, only Flynnery allows the hero a weapon to deflect attacks as well as dodging. Contrast Single Stroke Battle.
Bonus points if the hero uses the battle as a chance for quippery.
May sometimes be used for villains, but the fight usually lasts only a short time; a villain the hero can't hit tends to be seen as annoying rather than challenging (see The Vulture). Exceptions may be made for a hot villainess, since enough battle frustration may lead to due to Dating Catwoman possibilities.
Spider-Man is the trope codifier, as much as any single character can be when this trope plays so well to suspense buildup. Unless the plot requires it Spidey combines his agility, strength, Spider-Sense, and high marketability to dodge *any frakking thing* on the planet, and he loves to let people know it; see his Secret Wars beatdowns of the complete X-Men team, and Titania.
Iron Man: was literally redesigned after his early appearances to be less like the Mighty Glacier he looked like (after all, it's a big clanky suit of armor, and a pilot with all the combat experience you'd expect of a lab monkey) to a lighter suit more capable of some Evasive Action Hero moments. Still relies more on being Nigh Invulnerable, but also dodges plenty just to prove he's a real hero and the villains are real threats.