The Well of Arwan

From publisher blurb: The Well of Arwan is an adventure module set in the Mhâr fantasy RPG universe and playable in any regular fantasy RPG setting. Players will be set upon an adventure that will bring them in contact with the Hood and see them explore the long buried ritual site of an ancient druidic cult as a Necromancer and his servants seek to unlock the gates to the underworld. This module includes the setting details of Malsprydd Castle and rules for introducing Necromancy to the game.