You know, as I was writing my earlier response, the thought of a Minotaur and a Gryphon came to mind as well. The Minotaur would be easier, given he stands on two legs and can wield swords with his hands. They Gryphon would surely be harder to write, unless you set the good Beast up as more of a strategic General and not one who could help the Kings practice in their training (which is why Sir Leszi is there then).

And I must admit, now that this story is done, I spent a good majority of my work hours today re-reading "By Royal Decree". You can get a deeper meaning to the relationship between Jalur and Edmund now, and I was struck by how accurate Mr. Hoberry's description was: the Tiger truly does "manage" Edmund!