The MCU loves a good redemption story and cybernetically-enhanced (and perpetually tortured) "Daughter of Thanos" Nebula represents one of the franchise's very best "180s." Violently resentful of favored child Gamora, and constantly seeking Thanos' approval, Nebula did the Mad Titan's bidding without question. Eventually, Nebula came to recognize Thanos' "love" as abuse, and Gamora as a true sister. By the time Endgame rolled around, she literally executed the past version of herself to save her new comrades.
10/10