Minecraft was released by Mojang in 2011 and its cave ambience became one of its most recognised audio details. The game plays these randomised sounds when a player is underground in a dark, enclosed space, with no visible source or warning. Files in the game are numbered, which is why clips circulate online as Cave Sound 15 and other numbered variants. Outside the game, the sound spread through gameplay videos, creepypasta edits and horror memes, and it remains popular because a few seconds of it instantly signals danger without showing anything on screen.