The Scarlet Oracle Demetria
Demetria <The Scarlet Oracle> is a level 61 elite human found in the Eastern Plaguelands.
Background
Demetria is chief adviser to the Grand Crusader. She is called the Oracle due to her 'otherworldly' senses. She has successfully assisted the Scarlet Crusade in several of their victories against the Scourge.
She is always guarded by nine absolutely loyal Scarlet Troopers, when leaving Tyr's Hand, a headquarters of the Crusade. But even alone she is a powerful enemy, resurrecting her guardians, healing herself and killing her enemies with mighty magical attacks.
Demetria must be slain to complete the quest 
[60E] The Scarlet Oracle, Demetria, the final quest in a chain started by Nathanos Blightcaller.