When Blizzard introduced the God of Blood - Hakkar to his mates - in a new World of Warcraft scenario called Zul'Gurub, little did it know it was summoning up the online equivalent of Ebola or AIDS.
According to a posting on WoW fansite Shacknews, anyone who ends up in a fusticuffs-style confrontation with Hakkar will be attacked with a magic spell called Corrupted Blood. It's a nasty one. There's little the victim can do to resist it, and it should do sufficient damage to wipe them out.
Except sometimes it doesn't.
The result: infected players become themselves infectious, and have started passing the plague on to other characters. WoW being an online game, with the virtual world ticking over while players pause for pizza, pee breaks and - now and then - forty winks, the contagion continues to spread from non-player characters to non-player character and anyone else entering the game.
As the poster claims: "Some servers have gotten so bad that you can't go into the major cities without getting the plague. And anyone less than like Level 50 nearly immediately die."
It's said that attempts have been made to quarantine the infected, but the efforts of what might be called the World of Warcraft Health Organisation (WWHO) appear to be ineffective. Plague-carrying players escape the curfew to lug the lurgey out into the wider WoW world.
The Corrupted Blood disease is, in short, out of control and rapidly taking on epidemic status.
WoW has more than 2m of players around the (real) world, Blizzard said in June. How many of their virtual incarnations are at risk remains unknown. We're awaiting comment from Blizzard.
The Zul'Gurub scenario was introduced last week with version 1.7 of the game. ®