Partway up Erodan Mountain stands the temple of a secret order, dedicated to an ancient serpent goddess. Although clandestine in nature, the priests and priestesses of this temple were many, for they guarded jealously a precious artifact that once belonged to the goddess they served. But in recent years, this order has perished, for a mysterious plight has befallen its members, and those who dare to enter are never seen again, lost amidst a hail of shrieking voices and a thunder of iron. Includes 5E adventure The Serpent`s Stone.