The Strangling Sea

From the publisher's website:

Experienced seafarers know better than to risk the dangers of the Stranglesea: that terrible place where castaways cling to existence in the rotting hulks of trapped ships, and deadly creatures feast on the unwary.

Now a band of adventurers must enter the Stranglesea and attempt to rescue the enigmatic engineer Inigo Sharpe from his imprisonment. But Sharpe is both more and less than they were prepared for — and the forces of an enemy icon want him for their own sinister purposes.

The Strangling Sea is a seafaring 13th Age Roleplaying Game adventure by Robin D. Laws for a party of 4-6 1st-level adventurers.