The sound comes from Team Fortress 2, Valve's team-based shooter released in 2007, where Heavy Weapons Guy is the slow, powerful class known for his deep voice and minigun. Players began clipping his exaggerated voice lines for jokes and animations, and the Pootis Pow laugh became a shorthand for triumphant, overconfident humour in gaming communities. It spread through YouTube edits, Source Filmmaker videos and soundboards, where short recognisable character clips are easy to reuse. It remains popular because the laugh is instantly readable even without context, turning a simple win into a joke.