Power of Three
Diana Wynne Jones
 The story begins when two Lyman siblings, Orban and Adara, accidentally revert a shapeshifted bird on an English moor back into a small Dorig. The Dorig is holding an exquisitely molded collar, which in Lyman and Dorig culture are used to store protective magic. When Orban tries to take the collar, the Dorig says he is the son of the Dorig king, and will curse the collar before giving it up. Orban kills the Dorig and takes the collar anyway, and as the Dorig dies he binds a curse to the collar by the three Powers - the Old Power, the Middle Power and the New Power. Orban grows up to be chief of the Otmound mound. Adara marries Gest, chief of the Garholt mound, and has three children: Ayna, Gair, and Ceri. At a young age, Ayna and Ceri discover they have powerful magical talents called "Gifts" - Ayna has precognition, and Ceri can find anything when asked. Gair, the middle child, becomes increasingly gloomy when he fails to develop a Gift. When Gair is twelve, the Dorig - at war with the Lyman ever since Orban killed the prince - flood the Otmound mound. The Otmounders move into the Garholt mound, bringing with them bad luck which gets worse and worse. Ayna, Ceri, and Gair are exploring the moors one day when they come across two young Giants, whom the siblings follow back to their house. When they are discovered, a cultural exchange takes place. The Giants inform them that there are plans to flood the moor to provide drinking water for England. The siblings, the Giants, and two Dorigs must work together to stop the Moor from being destroyed. The bad luck is found to be emanating from the collar Orban had stolen from the Dorig prince, still strongly cursed. The three races can deactivate it together, or not at all. It turns out that Gair is not so ordinary as he had expected himself to be. His fame grew later throughout the Moor and was known for his magnificent collar, of the finest Dorig work. He was also known to have the rarest Gift of all, and that is the Gift of Sight Unasked.