Pathfinder Adventure Path: Strange Aeons Part 6 of 6: Black Stars Beckon

Arriving in the alien city of Carcosa, the adventurers must sever the links that bind Carcosa to Golarion. Can the heroes keep Carcosa from drawing Thrushmoor into its amalgam of stolen cities or do they risk waking the unspeakable nightmare that stirs in the depths of Lake Hali?