The Marvel Cinematic Universe may be a bastion of inter-franchise connectivity, but even its Avengers can't be everywhere at once. Over the course of fifteen years, which have encompassed more than forty different films, series, special presentations, and one-shots, the MCU has developed a sweeping roster of superheroes to make up the Avengers. However, the MCU hasn't always been able to address the whereabouts of Earth's Mightiest Heroes in every film and series, even those that contain massive threats. As a result, the MCU has included several irritating moments wherein Avengers-level threats went unaddressed by the iconic superhero team, leaving only a handful of heroes to deal with each.

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