The Sentry Buster was introduced with Team Fortress 2 and its Mann vs Machine co-op mode in 2012, as a giant robot designed to rush Engineer buildings and self-destruct. Its distinctive spin signals the detonation sequence in-game, warning the defending team to move clear. Clips of the sound later spread through gaming videos, soundboards and meme edits, where the short warning became shorthand for any unstoppable threat about to explode. It remains popular with TF2 players because the cue is instantly recognisable and carries the whole joke without any dialogue or explanation needed.