They come upon a fight between Friday's flying troops and Saturday's troops. Arthur helps defeat the latter, and in return Friday's servants take him to their nest, where they find the fifth part of the Will, which takes the form of a creature with body parts of different animals. Then they go to Friday's scriptorium, where the Piper orders Ugham to take what looks like the fifth Key. It turns out to be a trap that opens a 'void' that starts to grow. Arthur is forced to use all four Keys in his possession to close it.