Mixed Magics, or, short stories of Chrestomanci
Yay, Chrestomanci stories! DWJ wrote more Chrestomanci stories than anything else, but there are not enough of them. The four short stories:
"Warlock at the Wheel" stars the Willing Warlock from Charmed Life, who escapes from the law to our world. He steals a car, and from then on it's pretty much O. Henry's "Ransom of Red Chief," as a demanding little girl and her giant guard dog torment the poor Warlock into a breakdown. It's funny, especially for younger kids ($5 says it also started as a bedtime story!), but not stellar.
"Stealer of Souls" is a fairly recent story, published in 2000 and only in this collection. Tonino Montana visits Chrestomanci Castle, and Cat is charged with looking after him (this takes place some time after Charmed Life and just after Magicians of Caprona). Cat is an utter brat about this and dislikes Tonino, but then they are both kidnapped by a terrifying evil wizard who has spent the last couple of hundred years collecting lives from nine-lifed enchanters. With their memories stolen, and forced to cope on their own, Cat and Tonino become a team. I love this story; I think it's a great addition to the Chrestomanci tales.
"Carol Oneir's Hundredth Dream" is another particular favorite of mine. It's from 1986, which means it was written just before (or I think more probably at the same time as) The Lives of Christopher Chant, and in the timeline it takes place right after "Stealer of Souls." Carol is only about eleven, but she's a highly successful professional dreamer. When all of a sudden she can't dream any more, her father calls up Chrestomanci for a consultation. Chrestomanci expertly dissects Carol's dreaming methods and delivers her from her stage mother as well.
There are two fun elements about this story: DWJ both explained and poked fun at her own writing methods with Carol's dreaming cover story and her real, inner thoughts -- which are both true, despite the contradictions. Then, Carol's father is the Oneir who smashes Christopher's head with a cricket bat....and "oneiric" means "having to do with dreams."
"The Sage of Theare" is also one I'm very fond of. In an extremely orderly parallel world, the gods are worried about the prophesied Sage of Dissolution, who will destroy them. In a bid to stop him, the sun god finds curious little Thasper and takes him to another world, but that causes some serious difficulties. Chrestomanci has to help Thasper and deliver a stern lecture to the gods. This story is a standard selection and appears in a lot of the DWJ collections.
So, three really great stories and one fairly good one.