Long ago, in the Time of Black Thickening, the shadow demon Xulthûl (zul-thool) gained physical substance and walked the Realm of Aethos, a gruesome thing of clotted darkness sheathed in a skin of malice.  Before Xulthûl, no mortal could stand, no army could prevail, and Aethos descended into depravity and blight.

So vivid, however, were the horrors that Xulthûl’s incarnation wrought upon the living that their anguish roused the Avatars of Aethos.  Noble beings of purest Light, the avatars took pity on the mortals of the Realm.  They assumed human form, secured the great strongholds of the Realm, and unsealed the Wells of the Ancients hidden within.  The cleansing Light of the Wells flooded into Aethos, dissolved Xulthûl’s material substance, and drove it back into the Shadow Realm.

Yet even time forgets.  As the decades that followed Xulthûl’s defeat bled into centuries, the Wells of the Ancients faded into legend, the Guardians stationed within the great strongholds slipped into stone slumber, and the strongholds themselves fell into ruin.  Memories of Xulthûl dimmed into the stuff of nightmare, for what is the cold hatred of a shadow against the warm light of reason?  But banishment is not destruction.  Secure in the Shadow Realm, concealed behind a veil of disbelief, Xulthûl fed upon the fears and sins and dark desires of the very mortals that denied its existence.

As Xulthûl’s strength returned, its malign influence began to leak once more into the Realm of Aethos.  Wispy tendrils of perversion slid over and through the Realm, gradually transforming its lands into twisted tangles and its denizens into terrible beasts.  The Guardians of the Wells gradually lost the ability to distinguish Light from Shadow and rose up to destroy any creature that entered the strongholds they defended.  Even the Wells of the Ancients began to fall Dark under Xulthûl’s corruptive maleficence, slowly changing from channels of Light into conduits of Shadow. 

It is here that you enter the story, players, as the Avatars of Aethos returned.  At the start of the game, there will be sufficient Light Wells remaining to thwart Xulthûl, but their whereabouts will be unknown.  It will be your task to find the strongholds that contain the remaining Light Wells, defeat their Guardians, and unseal them… and with their cleansing Light prevent Xulthûl from gaining the corporeal substance it requires to physically enter the Realm of Aethos.

But be warned: Xulthûl will act against you.  It will spawn manifestations of its wickedness in the Shadow Realm and send them into Aethos with one unwavering purpose: to find but a single Light Well, and with its power provide Xulthûl the means to once again thicken the darkness into a skin of malice...