Computer virus of a different kind.

[Catweazle]

A plague has swept the online universe of popular game World of Warcraft! Cities have been wiped out. Travel became a dangerous activity indeed. Online gamers returned from a nature call to find themselves amidst desolation!

When Blizzard Software released the version 1.7 Patch for the online game they included a new event to join those already available, but it has had unforseen outcomes. Zul'grub, apparently, is a 20 person raid event in which groups of players can attack a perilous Troll city. Inside the City is Hakkar, God of Blood who has the uncanny ability to infect nearby players at random with 'infected blood'. This causes a large 'hitpoint' loss over a short period of time, and can be transmitted to other characters nearby whilst still 'infectious'. What wasn't forseen, however, was that if players who were affected used a 'hearthstone' to teleport back to their ingame native city, they carried the infectious disease with them to spread!

Hundreds of 'low-level' player characters died when this occurred, many high level characters spread the plague further, and even high level non-player characters became carriers. Chaos reigned in World of Warcraft.

From recent reports, the result has been chaos on many game servers!

[jwenting]

Interesting. So even Blizzard aren't immune from the phenomenon of forgetting to test sideeffects of changes outside the immediate context of those changes.

[tgreer]

I don't play this game, but find the above account to be hilarious. Why was this effect "unforeseen"? Presumbably infectious people/characters/avatars spread diseases. That's the very definition of "infectious". Of course this would happen! Hopefully the game developers won't "fix" this, as it is a realistic depiction of a real-world epidemic. Game players should have to adapt to cope with this new turn of events.

[jwenting]

The problem is apparently that they didn't intend the PCs to stay infectious after leaving the game area.
This is totally justified in an online environment where PK'ing (player killing) is by rule only ever to be consentual (killing others outside a formal duel is considered murder, killing players well below your own skill level is unsportsmanlike, both will get you a bad reputation).
As mainly lowlevel characters are killed off, this bug if left unchecked will soon make the game impossible to play for all but the existing group of veteran characters. Some of those won't mind that so much (there are groups of high ranking players in all MMORPGs who consider beginners to be useless annoyances that the game would be better off without) but that can't be the purpose of a game (especially economically as it will quickly mean noone is left playing it).