User blog comment:NoNickNeeded/Urano Metria power source?/@comment-5268982-20130901094404/@comment-7418318-20130901094938

Maybe Crux taught her the spell at some point of her training.

While we only see her training with Capricorn, that doesn't mean this was all she did. Just like we didn't see her get Pyxis and yet she has his?... it's key.

Since both Brain and Hibiki were able to access the same information on Nirvana from archive, I guess that means archive is a "shared data storage" so to say to which anyone with the magic has access. So most likely Hibiki just found it in there while browsing through the "archive net".

But who could have deposited it there I have little to no idea.