This clip comes from Team Fortress 2, Valve's team-based shooter, where the Demoman is the Scottish explosives expert whose taunts give players a short, characterful sound to play in matches. Fans clipped the taunt and gave it the nickname Hello Gundorf, passing it around in memes, edits and soundboards where a two-second shout was easy to reuse. It has stayed popular because it is instantly tied to the Demoman's personality, works without any game context, and fits the fast, joke-first style of short-form video.