Wu Jen
Wu Jen are an Arcane Spellcasting class present on the more Chinese flavors of Dungeons & Dragons. They combine the traditional Wizard spellcasting abilities with Ki powers and neglectful personal hygiene.
Advanced Dungeons & Dragons
The Wu Jen appeared in AD&D in the Oriental Adventures by Gary Gygax. They were identical to Magic Users in the Players Handbook with the exception of Ki Powers that were gained as they advanced in level and a Taboo that must be selected at 1st level. Violating this taboo resulted "in the loss of spells, illness, or other evil events" (Oriental Adventures, pg 26). Most taboos were related to issues of personal hygiene such as bathing or the cutting of hair.