The sound comes from Super Smash Bros., released for the Nintendo 64 in 1999, where an animated crowd reacts live to the action in each match. When a fighter lands a huge hit or is launched toward the edge, the audience gasps together in shock. Players remembered that exaggerated reaction long after the game, and clips of it were later isolated and reused outside the game. It now circulates in meme edits and gaming videos as a universal sign of disbelief, separate from the original match context.