Hakkar - the god of Blood.

A deadly virtual plague has broken out in the online game World of Warcraft.
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In the last week, it added the Zul'Gurub dungeon which gave players a chance to confront and kill the fearsome Hakkar - the god of Blood.
In his death throes Hakkar hits foes with a "corrupted blood" infection that can instantly kill weaker characters.
The infection was only supposed to affect those in the immediate vicinity of Hakkar's corpse but some players found a way to transfer it to other areas of the game by infecting an in-game virtual pet with it.
This pet was then unleashed in the orc capital city of Ogrimmar and proved hugely effective as the Corrupted Blood plague spread from player to player.
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The "Corrupted Blood" plague is not the first virtual disease to break out in game worlds. In May 2000 many players of The Sims were outraged when their game characters died because of an infection contracted from a dirty virtual guinea pig.

Reading this, though I'm sniggering, I feel out of touch. I'll have to get my seven year old to explain it.

Gary Gygax, what have you wrought?