From publisher blurb:
The Strange Aeons Adventure Path draws to a stunning conclusion! Arriving in the alien city of Carcosa, the adventurers must sever the links that bind Carcosa to Golarion. In wandering the parasitic city the characters navigate the frozen ruins of an elder thing city, deal with accursed partygoers in a reflection of an Azlanti city, and encounter a mute musician who can help them find their way in the maddening streets of lost Carcosa. 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? They must break these links—or Golarion is doomed to greet the King in Yellow.
“Black Stars Beckon” is a Pathfinder Roleplaying Game adventure for 15th-level characters. The adventure continues the Strange Aeons Adventure Path, a twisted delve into madness that pits the heroes against the cosmic horrors of the Cthulhu Mythos. A selection of new monsters, a look into the past of Golarion, ideas for further adventures beyond the bounds of the Strange Aeons campaign, and the final installment of a new Pathfinder’s Journal round out this volume of the Pathfinder Adventure Path.