The Castle of Death

From publisher blurb: The party has now recovered three sprigs from the elemental world trees, but the last looks to be the most difficult. Having discovered the final resting place of the sprig, they must travel beyond the edge of the map, into uncharted waters, and overcome the army of terrible dragon just to enter the final dungeon where the sprig is through to dwell. Can the adventures overcome the challeges of this third and final edtion from the Ice on the Water trilogy? This is the third and final part of a trilogy, and is created for 5-6 characters, levels 10+? The adventure is available in both AD&D and 5th Edition mechanics.