Everything you need to understand or teach Sir Thursday by Garth Nix.
Arthur Penhaligon's search for the Keys to the Kingdom continues. He has already uncovered the first three Keys and the first three parts of the Will of the Architect. Now he must continue his fight against the Morrow Days to uncover the remaining four Keys and Wills. For Arthur to succeed in his quest, he is forced to use sorcery. However, if he uses it too much he will become a...