Four: the snakes themselves. Wonderful characters. Loved their 'mating ball' quips.
Five: Lydia. Macabre, creepy and yet loving.
Six: how the circus moves. Jaw-droppingly marvellously inventive.
Seven: the flying. OMG, ever since I saw David Copperfield do one of those flying acts, I've wondered what it would be like. Other than absolutely wonderful.
I really, really want to run away and join this circus.