Narwol's Death Shroud

Origin
It was originally discovered by Kestral in his closet, and offered to any hero who could guess what it did without using magical means. This was at the Tournaments of Even Colder Moon in 999. It has a companion artifact (in that one bore a similar name) known as Narwol's Scrying Egg.

Description
Narwol's Death Shroud is a rectangular magical blanket that is thirty feet in circumferance.

Effects
Cain was the first to guess that it was capable of the spell "Group Healing", as judged by it's approximate size. When identified magically, it was identified that Seer magic was particularly weak against it, but that it was "weaved by skeletal hands". Nothing else is known about it.

Source
http://library.cityofivory.org/460/Narwol-s-Death-Shroud