Dupe is one of the trick entities in Roblox Doors, a horror survival game where players move through numbered rooms while avoiding monsters. Instead of attacking openly, Dupe creates a false door number, so a player who trusts it walks into an ambush. Clips of that moment spread through gameplay videos, streams and short-form edits, where the sound became shorthand for being fooled. It remains popular because the joke is instantly clear: someone thought they were safe, picked the wrong door, and got duped.