This sound comes from Counter-Strike: Global Offensive, Valve's tactical shooter where terrorists plant the C4 explosive at a bomb site while counter-terrorists try to stop or defuse it. The planting audio has become instantly recognisable to players through years of competitive matches, streams and highlight reels, where a successful plant often turns a round on its head. Editors later lifted the short beeping sequence for memes and short-form videos, using it as shorthand for something about to blow up, a risky plan in motion, or a deadline running out.