Knight of shadows.

Book 9 of the Chronicles of Amber. Merlin has called a truce with one enemy, only to discover another that hits far closer to home. Despite his power over Shadow and Chaos, he finds himself caught in a web of design and deceit, forced to choose sides between his two heritages. Can he find the allies he seeks in time to save himself from a complete division of loyalties? Can any child of Amber choose their own destiny, or is its pattern laid out before them from birth?