With an enemy fleet intent on conquering the Shackles looming on the horizon, the adventurers must build their own fleet of pirates and buccaneers to defend against the invaders, culminating in an epic naval battle in the middle of the Eye of Abendego. Will the adventurers defeat the invading navy and save the Shackles? Or will the independence of the Free Captains be eradicated forever? A Pathfinder Roleplaying Game adventure for 13th-level characters, this volume concludes the Skull & Shackles Adventure Path. From Hell's Heart also presents a host of options for GMs looking to continue their Skull & Shackles campaign, along with details on the deadliest sea monsters said to lurk beneath the waves. New monsters from the depths of the sea and exotic islands also fill the Pathfinder Bestiary, while Robin D. Laws (author of the Pathfinder Tales novel The Worldwound Gambit) concludes his tale of pirates and lost treasures in the Pathfinder's Journal.