Hi. I just checked with a site online (my character is a level 50 Storm Wizard, but I could not recall any firm details about this spell so)..
According to what I read on the Wizard101 Wiki site, it appears that you get the spell at the end of Marleybone.
The site mentioned that the Quest was called "Bad News" (I think) and that it involves talking to Merle Ambrose before your character heads off to Mooshu.
Hope that helps. And I hope the info is correct too.
