There Phase 4 of the mcu introduced an extraordinary number of new superheroes to the franchise. Launched in the aftermath of Avengers: Endgamethe Phase 4 of the mcu was about expansion: the shared cinematic universe evolved into a transmedia multiverse, and included much more content than Phases 1-3.
This also means that the Phase 4 introduced more superheroes while preparing the introduction of even more. In fairness, this list only includes live-action heroes who have had a chance to develop as characters, not heroes like theHercules Of Brett Goldstein appearing briefly in post-credits scenes, or heroes we expect to meet, such as Black Night Of Kit Harington.
The last place, unfortunately, belongs to the Mighty Thor Of Jane Foster. Introduced as little more than a love interest for Thorthe character of Natalie Portman had been underdeveloped and loosely written out of the mcu. He then went back in Thor: Love and Thunderclaiming the enchanted hammer Mjolnir of Odin in an adaptation of one of the most influential comic book storylines of the last decade.
Unfortunately, the film failed to capitalize on Mighty Thor’s potential; the version of mcu The character lacks a real sense of will, having gained his powers only with Odin’s blessing. All in all, Mighty Thor was therefore an almost totally wasted character.