7. A Brooding Black Widow
Black Widow found herself falling for Bruce Banner in Avengers: Age of Ultron. It came out of nowhere but, whatever, audiences seemed to accept it as legitimate. However, his abrupt exit in order to distance himself from civilisation - he flew off in a S.H.I.E.L.D. Quinjet to parts unknown - left her sad and contemplative at the movie's climax. Having shown that she does actually have feelings, this will undoubtedly continue in Captain America: Civil War - and it will surely have an effect on her performance on the battlefield. How that manifests remains to be seen. Whether it will distract her, resulting in her not being at the top of her game, or whether she's so pissed off that she's an even more dangerous combatant than usual, you can definitely expect there to be a noticeable change in the former assassin.