The Invisible Hand by Chris Northern

The necromancers power base is destroyed and the source of their power, the Grave, is flooded. Darklake is crammed to bursting with refugees after I sacked the Grave and destroyed Learneth by fire. Darklake, Learneth, the Grave are mine by right of conquest. Now I have to decide what to do with them. I just hope I decide wisely.