Left 4 Dead is a cooperative first-person shooter developed by Valve and released in 2008, following four survivors fighting through hordes of infected. Its audio design became widely recognised because short cues warned players about attacks, special infected and sudden danger during chaotic rounds. As gameplay clips and edits spread on video and soundboard sites, individual effects were separated from full matches and reused out of context. This clip survives in that form, used by creators who want instant zombie-game tension without needing any footage from the original campaign.