COC is shorthand for Clash of Clans, the Supercell mobile strategy game released in 2012 that became one of the most played phone games of all time. Its coin-collect chime is part of the game's signature reward feedback, heard whenever players gather gold and elixir. The sound migrated to memes and short-form video as creators reused game audio for comedic reward moments, turning a simple collect effect into shorthand for easy money. Its popularity endures because the chime is instantly legible: two seconds of audio that says payday with zero explanation needed.