Oh dear god, I've forgotten about the horn. How are they going to work that in? Seems like something that should have been seeded already. Between that, Val and Dalla, the Thenns, there's a lot of missing pieces up North.

Robb isn't a point-of-view character in the books, so everything you know about him is revealed from a distance through Cat — and even she doesn't have very much access to him. There really isn't much source material to work with, and the vagueness of it all seems to be translating to the screen.