Beyond the Grave: Tamriel's Undead

Excerpt
''Powerful and aggressive, wraiths are spirits full of hatred for the living. They do occur naturally, and most studies suggest that they are formed from individuals who suffer great injustice and leave important work undone. Unfortunately, in limited attempts to engage with them, they will not speak.''

''If they have any recollection of their lives or the circumstances around their deaths, they make no display of it. In some cases, exceptionally dangerous necromancers have discovered methods by which to create these hateful spectres and enslave them as guardians. It is recommended to avoid any place rumored to contain wraiths, as their threat to the living is extreme.''