The line comes from Yu-Gi-Oh, the manga, anime and trading card game series where Trap Cards are hidden cards set face down and activated when an opponent meets their condition. Players and fans turned the dramatic declaration into a meme for any perfectly timed ambush or reversal, sharing it across forums, videos and soundboards. Its appeal comes from how specific the game mechanic is yet how broadly the joke applies, so it remains a shorthand for catching someone out exactly as planned.