Team FC
Imprisoned alongside Tony Stark in Iron Man (2008), Yinsen helped the industrialist develop a suit of armour as opposed to the weapons they were ordered to make, and later gave up his life for Stark, thus helping the MCU come to life.
In Black Panther (2018), M'Baku was defeated by T'Challa after he challenged the latter for the throne of Wakanda. T'Challa spared M'Baku's life, and the character saved his king's life later in the film and even battled Killmonger's forces alongside him.
One of Loki's early opponents, the character proved to be valuable across multiple films, coming to the aid of different combatants caught in a fix.
Cho not only saves Hawkeye's life but also plays the most significant role in neutralising Ultron when he gets up to no good.
Erskine created the serum that would create a supersoldier and hand-picked Steve Rogers to be Captain America, pretty much creating one of the chief elements of the Universe.
Thor's mother met him during a time-travelling mission and helped him regain his determination and sense of purpose.
She came to the aid of Captain Marvel and Nick Fury when she had none of the superpowers they possessed. Despite the fallibility that came with being a regular human being, she went above and beyond to help people in need.
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