Battle Born by Amie Kaufman

Though Anders and his friends have delayed a war between ice wolves and scorch dragons, their mission is far from over. With adults on both sides looking for them, they’ve sought refuge in Cloudhaven, a forbidden stronghold that could hold the key to saving their home.
Meanwhile, Holbard has been ravaged, and its citizens are reeling. Many have been forced into bleak camps outside the city, and food is running short.
To rebuild Vallen and unite scorch dragons, ice wolves, and humans, Anders and Rayna must put everything on the line…before the damage done is beyond repair. But the price of peace may hit closer to home than they could’ve ever imagined.