From publisher blurb:
You have travelled to the westernmost point in the Duchy of Starryshade as you make your way to the borderlands. Your final stop in the duchy is a small roadside inn called the Shepherd’s Spear Inn. While stopping for a respite you hear a few tales including a mysterious abbey nearby. This structure is said to only appear for a short time every three years. Magic and wealth are said to be lost within the walls of this structure and with little else to do this might be a final hurrah for your stay in Starryshade!
This adventure setting was designed for 5th Edition AD&D for the Filbar Campaign for mid-level adventurers and DM. This adventure is easily adaptable to most any game and system. Save yourself some time and utilize it for a one shot adventure or a continuing campaign!