The quack comes from R.E.P.O., a co-op horror extraction game by Semiwork that players began sharing widely in 2025. Its duck monster, often called the Apex Predator, looks harmless and follows players while quacking, but turns aggressive if provoked, creating a contrast that made clips easy to share. Streamers and editors clipped the short quack for TikTok, Shorts and Discord soundboards, where it became shorthand for a cute follower that is secretly dangerous. Its brevity keeps it reusable as a reaction sound long after the original scare.