The End of Nobility — Michael Green

It's Ender's Game meets Children of Blood and Bone, set in a world where everyone has access to food, shelter, and magic, but the children still live in fear. The draft is in effect. When the army attempts to draft Dre and Alaan, the first and only twins, and Rye, the son of a disgraced soldier, they know something is wrong. By the time they realize how wrong, they are running for their lives with assassins after them. To survive, the twins will have to wield their fame as a weapon and Rye will have to dig deeper into the truth of his father's disappearance.