From the Shadows (Advanced Dungeons & Dragons, 2nd Edition Rq3)

Deep beneath the foundation stones of Castle Avernus, Azalin the lich hatches his plots. The grand conjunction is coming, when all the lands and lords of Ravenloft will be set free upon the realms of man. Azalin does not intend to let this oppurtunity slip by. All he needs are a few dead bodies. Fortunately, there is a party of adventurers nearby...
This is the first of two adventures that feature Azalin the lich and Strahd von Zarovich in their eternal conflict. This module contains complete floorplans for Azalin's dark home, Castle Avernus. From the Shadows will take characters to places they've never been before - places spoken of only in hushed whispers and terrifying legends.