Sorry for being the one that shits in everyones cornflakes but..
"Transmogrification Item Restrictions
Well, I don't want to be the bearer of bad news, but...
We have an obligation to players and to our hard working artists to keep the game from looking too silly. I know looking ridiculous is fun for some players, but World of Warcraft was established with a design that the game overall kept its silliness in check. That’s one of the reasons we resisted adding a feature like Transmogrification for so long.
So weapons that look like fish, for example, probably won't be available as source items for Transmogrification, even if one is technically a dagger and has stats. There are a handful other weapons with "silly" models (such as frying pans, brooms, etc.) that may or may not be allowed -- it's still under discussion. (Blue Tracker / Official Forums)"
"Can you Transmogrify BoA items?
We likely won't allow heirlooms to be transmogrified. (Blue Tracker / Official Forums) "
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