The unique affix, while it does not relay to any specific skill, only affects Necromancers. It simply reduces all damage taken (multiplicatively to other similar effects) the lower the Necromancer is in Life. Note that damage reduction is calculated before the hit, so at full Life, it will not give any protection. This effect works best against damage over time or many weak attacks, but works significantly worse against single powerful blows.
Stats (Level 39)
Forged to protect a loved one, this ring gleams with its own perfect light.