The first of the twelve artifacts has been recovered: the Shroud of Skelos. Here's a brief overview of the artifact:
The Shroud of Skelos
Created by the archmage Skelos to assist him in his campaign against the undead, the wearer of the Shroud is invisible to all undead (unless he attacks, in which case the invisibility ends). Moreover, if the wearer has suffered a level loss from contact with the undead and sleeps one night while wearing the Shroud, he is afflicted with terrible nightmares which he must conquer with a successful Wisdom check (CL the number of levels lost). If he makes the check, he regains the level as per a Restoration spell. Only one check can be made per person per week.
You can read the details about their discovery of the Shroud here.
One thing I did love about the session. I play with a group of almost complete novices, and their pure terror and wonder at the discovery of a gelatinous cube (the Roomba of the dungeon) was a sight to behold.