Blade of Decay

A Blade of Decay is a short non-unique weapon used by undead warriors on very rare occasions.
If cut by the blade, the skin around the wound will turn black, and the affliction will spread to the whole body over multiple weeks, eventually killing the wounded person.
The blade disintegrates immediately after causing a wound. Any undead wielding it will be repeatedly resurrected until the weapon is removed from its possession.
It is not possible to heal the wound with conventional methods or regular healing scrolls.