Chaosbound: The Eighth Book of the Runelords

The world of the Runelords has been combined by magic with another one parallel it, the beginning of a process that may unify all worlds into the one true world. This story picks up after the events of The Wyrmling Horde and follows two of Farland's well-known heroes, Borenson and Myrrima, on a quest to save their devastated land and the people of the new world from certain destruction. But the land is not the only thing that has been altered forever: in the change, Borenson has merged with a mighty and monstrous creature from the other world, Aaath Ulber. He begins to change, becoming a berserker warrior with a huge new body. Thousands have died. Lands have sunk below the sea and, elsewhere, risen from it. And the supernatural rulers of the world are part of a universal evil yet play a byzantine game of dark power politics among themselves--a game in which Aaath Ulber is now the most significant pawn.