This sound comes from Pure Pwnage, the cult web series about gaming culture, where the character Jeremy says the line during the well-known “Boom Headshot” scene. The quote spread widely through early internet video sharing, machinima-style edits and shooter montages, then stayed alive in meme culture because it perfectly matches exaggerated kill shots and overconfident reactions. It is still used as a shorthand punchline for any clip that turns a simple hit into a huge moment, much like oof minecraft in gaming edits.