Note the title. Cause that's sort of what happens in Mythmaker III. All of the sudden, out of nowhere, there are mythical beasts introduced into a book that at no point has shown signs of being like a fantasy novel. Not like dragons are gonna start showing up or anything, but even I have to agree it is a little unusual.
Don't worry though. It'll all make sense. Sort of. I mean, as much sense as A Kind of Drug has made so far. Or did you forget the whole premise of the book was a written language that had narcotic-like effects? Tsk tsk.