The TF2 crit sound comes from Valve's multiplayer shooter Team Fortress 2, where it signals a critical hit dealing boosted damage. Over time, players clipped it into frag videos, edits and memes, and it spread beyond the game as a shorthand for exaggerated impact. Its lasting appeal comes from how short and unmistakable it is: even people who have not played TF2 often recognize it as a classic PC gaming sound used to sell a big moment.