Demonkin Demonstone Chronicles, Book 4.

As two continents prepare for a worldwide war, a small group of Alceans plot to free the Dielderal elves from the grip of the Federation. The goal is to make the elves simply disappear, but over a thousand elven children are held captive in the four major cities of the Federation, and the Dielderal elves will not flee while their children are endangered. Complicating matters are the 'births' of a new breed of demonkin, the Claws of Alutar. While...