The Wizard's Tower Issue 03: The Aquamancer

From publisher blurb: The Adventurers find themselves far from land in the deep ocean. A great floating tower, the dreaded Devil’s Barnacle, sails towards them. Can they escape the clutches of the Sea Lubbers and their captain, The Aquamancer? What follows is an OSR-inspired adventure to describe a wizard’s sea-borne tower. It is designed to be incorporated into your campaign world, using the rules you feel like using.