I'm partial to adding an incantation and a stern warning.
Edit: It occurs to me that the Animagus transformation doesn't require an incantation either, so that's not a general rule about free vs. non-free Transfiguration, and it's hard to imagine that an incantation like Crystferrium ("Furniporcis"?) wouldn't give away the direction. Just the warning, then.
Yes, the big thing that's missing is the warning not to try to copy her example. Anything else can be chalked up to the Professor's leet transformation skillz.
ETA: There is now a third thread, so send new comments there.
Since the first thread has exceeded 500 comments, it seems time for a new one, with Eliezer's just-posted Chapter 33 & 34 to kick things off.
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