The sound comes from Team Fortress 2, Valve's class-based shooter released in 2007, where the Heavy is the large Russian minigun class. Critical hits deal triple damage and trigger distinctive death screams for each class, and the Heavy's version became a favourite for extraction into soundboards and edits. Like the Roblox oof, it turned a routine in-game death noise into a standalone meme reaction. Players still share it in TF2 communities and gaming videos whenever a powerful character is dropped unexpectedly by a single lucky crit.