Apparently, it's not just because it's a World of Warcraft expansion, but because it shows too much bone:
Posted by Nicholas at March 13, 2009 04:05 PMStupendously popular online game World of Warcraft's second expansion, "Wrath of the Lich King" is being blocked by Chinese censors for showing too much bone.
According [to] JLM Pacific Epoch, China's General Administration of Press and Publication (GAPP) has twice rejected applications from Blizzard Entertainment and its domestic operator, The9, because of the game's all-too-frequent depiction of skeletons.
The original release of WoW had required Blizzard to modify undead characters and enemies in the game to pass Chinese regulator muster. Among the changes were giving the walking dead extra meat and using graves to show where players have died rather than skeletons.
China had issued the usual People's Republic governmentspeak, stating this is it's way of promoting a healthy and harmonious online environment.
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