The Pandora Core - The Dream Engine, #4

Eila, Eve, Abbie, and their small band of allies find themselves on the run again. Fleeing North from the all-but-ruined Waldron's Gate, they are on a quest to carry the precious core of the Blunderbuss to safety. But they are not alone. Pursued by a creature calling itself Leviathan, as well as by operatives from Waldron's Gate, and soldiers from Stensue, this rag-tag band has to draw on all of their collective courage and skills at each step of the journey. As the rebels press on, Juliette journeys to Athenia in a desperate gambit for allies and worldwide consensus on confronting the coming crisis.
But has she overplayed her hand? Their treacherous odyssey takes Eila and her friends through the lands of Thesic and Aerohead on their way to their ultimate destination: The Celestial Gate. The Pandora Core, book four in The Dream Engine Series, ratchets the tension up to eleven, turning the careful world of Alterra and its foes beyond inside out.