Escape from Aurora by Jamie Littler; the sequel to Frostheart.
This is a pre-order and the book is coming out on 1st October.
Ash and the rest of the Frostheart's brave crew have finally arrived at the majestic stronghold of Aurora - and Ash's mind is blown. It's an extraordinary place - unlike anything he's ever seen - and he can't wait to solve the next clue that will lead him to his parents. But it's quickly clear that even Aurora isn't safe for Song Weavers.
A fanatical Pathfinder captain has turned the city against Ash and his kind - and it's not long before the Frostheart has to make another break for freedom. But when a vicious Wraith attack leaves Ash, Lunah, Rook and Tobu stranded on the ice, they will have to use all their strength and cunning to reach safety. But what they find is even more incredible.