Pendulum, book 2: ShadowWill Elliott2011

The Wall at World's End has been destroyed and Levaal stands naked again before its twin world. The Arch Mage seeks to unseat Vous before he joins the gods, but loyalties are fractured, within the Castle and among the Free Cities, as war and chaos loom. And a dragon may have escaped its sky prison, while a new alien force is rising by the name of Shadow. When Eric Albright opened a door and entered Levaal he was truly a stranger in a strange land. Now the Pilgrim seeks answers, on the dragons, the gods, the demon being called Tormentors, and on the disturbing link between himself and the being known as Shadow...between our world and Levaal...