The Corrupted Blood Incident occurred in September 2005 within World of Warcraft when a debuff from the raid boss Hakkar the Soulflayer escaped into the game's major cities. What was intended to be a local challenge turned into a global virtual pandemic as players and NPCs inadvertently spread the highly contagious and lethal 'Corrupted Blood' spell, resulting in streets paved with player skeletons. The event is famous not just in gaming history, but also in real-world epidemiology, as scientists studied the player behavior during the crisis to model real-world disease outbreaks. In meme culture, it is used to reference chaotic outbreaks, unexpected glitches, or the absolute carnage of early MMO gaming.