The sound comes from Dark Souls, the 2011 action role-playing game by FromSoftware, where Mimics disguise themselves as treasure chests and attack unwary players. Hearing the death cry meant the ambush was over, and the distinctive wail stuck with players long after the fight. As Dark Souls gameplay clips, streams and soundboards spread online, the short cry was lifted out of its original battle context and reused as a shorthand for a trap backfiring. It endures because Souls fans recognise it instantly, while newcomers still hear a clear, comic moment of defeat.