The line comes from Team Fortress 2, the class based shooter released by Valve in 2007, where the Scout is the fast moving offense class voiced by Nathan Vetterlein. The conga became a popular taunt in the game, letting players form dancing lines instead of fighting. Clips of the taunt spread through YouTube gaming videos, Steam community posts and meme edits, and the Scout's call became shorthand for starting a conga. It remains used because the dance is instantly recognisable to TF2 players.