Marvel Rivals

This is rather straightforward. You simply need to land lethal headshots on enemy players three times in a match. The headshot has to be the killing blow, and you could end uo be counter-attacked. I would suggest targeting weaker DPS and Support characters like Spider-Man, Hela, Mantis, Jeff or even other Black Widows for easier kills.

Keep in mind, achievements don't pop until the match is over, but if you've managed to get three fatal headshots through the match, the achievement should pop at the MVP screen.