Unholy Aura

Unholy Aura is a historical Death knight talent which was located in the 7th tier of the Unholy Tree.

Background
All death knights can learn to exude a dark, raging battle aura that causes allied creatures around them to move and regenerate life more quickly.

Before Wrath of the Lich King
Prior to WotLK, Unholy Aura was possessed by death knight bosses such as Baron Rivendare. It did about 150 damage every 2 seconds to anyone in range.