Perhaps we could add mountain troll to the Laramie Lexicon. The following definition comes courtesy of the Bestiary section of the Harry Potter Lexicon.
Mountain troll - The mountain troll is very stupid. It stands twelve feet tall, with grey skin, a lumpy body, and flat horny feet. It exudes a powerfully awful smell, "a mixture of old socks and the kind of public toilet no one seems to clean." Its nose is full of what looks like lumpy, gray glue: troll boogers. Their language consists of grunting and pointing.
Why yes, although Magic Mountain Trolls appear nowhere in the Laramie Saga, it would still be an excellent idea to add in an entry. I find this part particularly relevant:
It exudes a powerfully awful smell, "a mixture of old socks and the kind of public toilet no one seems to clean."
I think there's a clear and relevant connection here.
Oh, you might also want to include this about some 'Trolls':
they seemed considerably more intelligent and less smelly. They spent all their time pacing the corridor in front of the Fat Lady's portrait, giving dirty looks to everyone who happened by
Yes, a troll armed with a big club, ready to protect that which is precious. Considerably more intelligent than those you cite first, and ready to dish out pain to evildoers. An asset to Wizarding society.