The Well of Echoes by Ian Irvine
Chimaera, was in my opinion the best in the series, The Well Of Echoes. I think that it is necessary though, to have read the former series,The View From The Mirror, to fully understand some of the concepts and questions raised in the series. But the way in which he linked the two series was very clever.
Overall I thought that it was a very gripping and well thought out book, one which could involve the reader, as is Ian's style.
The cliff-hanger ending has left me eagerly awaiting for the next series to come out, and I only hope that the new series up to standard compared to The Well Of Echoes.