Fate of the Dwarf Lords. Annals of the Nameless Dwarf, #6

The Nameless Dwarf begins a new chapter of his life in the up-and-coming town of Brink, now that he has worked out his penance and resettled his people in Arnoch, their ancestral citadel. He has everything a dwarf could possibly wish for-a gym, a beer hall, and a bawdy house across the road. But then a blood-stained dwarf staggers into town with a message of doom:Arnoch has sunk beneath the waves, its last line of defense against the attack of a five-headed dragon.
The one slender hope remaining to the dwarves lies in their distant past: the dwarf lords, who had been created for perils such as this. But for centuries, they have been in exile on Thanatos, a world in which every life form has one purpose-to kill. With time running out for Arnoch, Nameless must find the dwarf lords and persuade them to come home. But before that, he first has to survive them.