An assassin slain. A fleet prepared. A battle looms.

Jacob fears their time is running out. The full focus of Belldorn and Bollwerk's tinkers is centered on the construction of the carriers. While Jacob is concentrating on overseeing the work, he worries for Alice who faces a dire challenge of her own. They need to launch an attack on Ballern, but their forces cannot cross the Crystal Sea without the new warships.

To deploy their ground forces they must secure a base, requiring a strengthened alliance with the forest city of Karn. Surrounded by Acidwings and Cannon Bugs, Alice and Furi embark on a journey fraught with danger in hopes of solidifying the Stormborn alliance. Steamborn and Skyborn must stand together in the looming battle ... or both will fall.

Even as they prepare for war, an enemy takes advantage of their distracted attention and strikes Midstream. But they are not the only forces moving in the shadows. Owen and the fisherfolk are closing in, intent on giving Mordair, now Steward of Ballern, a farewell he'll never forget.