Avengers 4: 9 Ways Thanos Could Be Killed

8. Nebula Gets Her Revenge

There's a pretty rich thread of past mistakes and crimes coming back to haunt MCU characters: Loki was killed for defying Thanos; the victims of Stark Industries' weapons haunted Tony; Thor almost died because of his arrogant mistreatment of his brother - and because of the sins of his father; Bucky's assassinations came back to haunt him; T'Chaka's abandonment of Erik Killmonger came back to haunt his son...

In short, there's not a lot you can get away with or run from - the past always catches up with you. So there's some reason to believe that Thanos might be held accountable for his own crimes - specifically those against his "daughter", Nebula.

How fitting it would be for the Titan to be destroyed - as he was in the comics - by the daughter he turned his back on. After telling her that Gamora was his favourite and she was absolutely no good, seeing her realise her "worth" by throwing those accusations in his face (along with some sort of actual weapon) would offer delicious poetic justice.