A sub-trope of Red Herring
. a Chekhov's Herring is when something is presented in a way that makes the audience sure it will come back later, but it never does.
- The Avengers has two of these in the same fight. Iron Man's suit getting overcharged and the shockwave from Thor's Hammer hitting Captain America's shield both seem like tricks they'd use again in the final battle. Neither of them are.