Black Widow

Is the MCU version of Black Widow a superhuman or just a normal human? We have no idea – Age of Ultron revealed that she had quite a rough childhood, while also hinting that several experiments were conducted on her. She grew up to be a killing machine and the perfect spy, having tricked even Loki into giving away his plan (or did she?).

She has mad fighting skills, she is very useful with a gun (with any kind of gun, for that matter), and she is a great strategist, among other things. She beat Hawkeye at one time, she held her own against the Chitauri, and so on.

And her outfit is jaw-dropping.

However, she is still not as useful on the battlefield as the next characters on the list.

One more thing: Is she the one to switch sides in the movie?