The Necropolis

This is an Act 4 main quest, offered by Inquisitor Creed after completing the Betrayal at Fort Ikon quest.

Objectives

 * Enter the Necropolis
 * Secure the inner Necropolis Riftgate
 * Speak to Ulgrim at the Necropolis

Guide
Make your way through the Plains of Strife to the Gates of Necropolis, then north through the area to the (second) Necropolis Interior Rift. Nearing it will activate three waves of Chthonians who must be defeated  in order to activate the rift. After doing so, Ulgrim will appear next to the rift.

Rewards
Ulgrim will then offer The Bane of Cairn quest.