Vardr - Barrow Wights

Vardr, or Barrow Wights are undead from a bygone era. Scholars are unsure what determines their power in death, or even why they are undead. Current speculation is that their incredible power in life and occult rituals after death have rendered these beings as permanent guardians to their burial grounds. 
Also unknown is whether these creatures are true creatures of shadow, or if they are resultant from some other power. They range in strength from base undead to incredibly powerful foes who can channel magic and control their own sanctums. Grave robbers who manage to steal items from their barrows without destroying the spirit within will find the spirits dogging their every move, eventually driving the robbers to madness or suicide. 
Vardr who take a human life in the defense of their barrows become more powerful and add that human soul to army of subordinate Vardr who serve them in the afterlife. 
Base Vardr are skeletal in nature, with a faint glow emanating from their eyes. This glow, dissimilar to raw emissions of light energy, is known as corpselight. It is described as a sickly pale blue-green glow. More powerful Vardr may emit this glow completely, or if they are imbued humans, emit this glow as a flowing mist. The most powerful Vardr have grown past their corporeal bodies entirely and exist as specters, often depicting as they appeared in life. Individuals who have seen a specter and have not fallen into madness or died outright are rare. 
There are legends of some specters speaking with and or giving cryptic aid to adventurers but those tales often date to the 2nd Era.