Into the Maelstrom (Dungeons & Dragons Module M1) Original 1985 edition

Alphatia, the most ancient empire, land of arcane and obscure secrets. It has grown for centuries and its might now overshadows the cauldron of civilization. Some say the Alphatians come from elsewhere, but no one knows for sure. Beyond the scope of mortals broods an evil mastermind, still in darkness. Once a betrayed emperor of ancient Alphatia, now an entity of the Sphere of Entropy, he seeks revenge on the greatest empire and on the race of man. His plots brought a deathly fog on all of Norwold. Perhaps it will extend to the soutern nations. The matter is grave, so much that lords of the spheres have now to show their might. For them, it is time for mortals to intervene. Man defends his cause for him to earn divine favor. A great armada has been raised and able commanders must be found. Prove your worth, and the eternal portals of the sphere may open for you.