Nerub'enkan

Nerub'enkan is a Nerubian crypt fiend. She is a mini-boss of Stratholme, found on the Undead side. She protects one of the three Ziggurats that guard the entrance to the Slaughter House, where Baron Rivendare can be found.

Dungeon Journal
''Nerub'enkan was a fearsome warrior during the War of the Spider. Ultimately, she succumbed to her wounds and was raised into undeath as an obedient minion of the Scourge. Now the nerubian guards a ziggurat in Stratholme as fiercely as she defended her home in life.''

Soloing difficulties
Nerub'enkan is known as the hardest hitter of the three bosses that defend Stratholme's Spirit Towers. Her raw, unmigrated damage is somewhere in the 3000s. She is immune to all stun and immobilization abilities, and has a long range attack that doesn't necessarily require her to be in line of sight with that which she is attacking. Her web ability temporaily makes that person or pet lose aggro, causing her to attack any solo-ing hunters or warlocks who may be using a pet to tank.