The Eel's Skull is a disused fortress in the Shackles. It is situated on Nalt's Island located between Bag Island and Shark Island, standing at the edge of a sheer cliff on the northern expanse of the island's eastern shore.
At one time it was the fortress home of the notorious pirate Nalt Tarbrow. It is said that there are Ghol-Gan dungeons beneath the fortress, but Tarbrow destroyed the fortress in a fit of madness, and no entrance to any dungeon has been found in the ruins. Yet the lowest levels of Eel's Skull still hide an entrance to the ancient Ghol-Gani region of the Darklands known as the Sleepless Realm. The ruins are still visible from the ships passing and every sailor knows that wealth lies somewhere deep within the cursed castle's abandoned halls and caverns.
Only two adventurers are known to have emerged from the dread dungeons of Eel's Skull alive and both were terribly altered by the experience. No attempts restore either to full health or sanity. Their eyes remained blind and pupil-less, their skin remained ash white and they continued to tremor. One eventually committed suicide by setting himself on fire (as Nalt's own fiery end), while the other, a Pathfinder named Gelrue Palane, is last rumored to have set off for Besmara's Throne.
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