If anyone could give life to the story of Jason and Medea and vividly imagine celtic society two and a half millennia ago and tie it all in to the Arthurian mythology, it would be Robert Holdstock. The project started in a brilliantly imaginative fashion in Celtika; unfortunately, the beginning of this second volume is rather bogged down by summaries of the backstory and repetitive forebodings, and can be downright inept at some moments. It does introduce a few interesting new characters, such as the king's daughter Munda. It only really picks up with the journey to the Otherworld, focusing tightly on the tragedy of Jason's son Kinos. All the characters and themes will certainly be present again in the third volume. Repetition over time is one of Holdstock's longstanding themes. The story of Merlin in this trilogy is a reflection of the idea of the fading of magic as humans become increasingly insulated from the non-human world by technology and culture. I can guess that Merlin was born when humanity was very new (supposedly; probably culture is a lot older than Holdstock indicates it to be here), and when he dies, magic will be gone from the world.