In Avengers: Infinity War, in order to obtain the Soul Stone, Thanos has to sacrifice someone he loves. To thwart Thanos, Gamora tries to stab herself, but he turns the knife into bubbles.
Thanos stops Gamora from committing suicide so he can kill her himself, by throwing her off the cliff.
It seems like, for the sacrifice to count, you have to actually kill a person you love. It's not enough to just lose someone through suicide.
However, in Avengers: Endgame Natasha sacrifices her own life, with Clint actually trying to save her. So even though Clint loses a loved one, it wasn't he who made the sacrifice. Nonetheless he wakes up with the Soul Stone in his hand (and he can hold it without getting killed).
- Why did Clint receive the Soul Stone, even though he didn't sacrifice a loved one?
- Is it actually necessary to kill a loved one, or is it enough to just lose one?