The Scout is one of the nine playable classes in Valve's Team Fortress 2, a team-based shooter released in 2007, and his fast-talking Boston voice lines are quoted constantly in gaming memes. This particular 'FOOOO' shout circulates as a standalone soundboard clip rather than a named voiceline, so its exact in-game moment is not widely documented. Like other shooter voiceline memes such as the enemy spotted callout, it stuck around because short, shouty game audio slots perfectly into edits and reaction clips.