The phrase primera sangre is Spanish for first blood, the term competitive games use for the first kill of a match. Spanish-language game announcers deliver it as a formal callout, and players began clipping that callout for edits and soundboards. It spread through short gaming videos and meme pages where the first death in a match is treated as a turning point worth announcing. It remains popular because the meaning is instantly clear even to viewers who do not speak Spanish, and the short length fits quick cuts.