Haurchefant tells you of the heretics who follow a mysterious leader known only as Lady Iceheart, and asks you to go to Whitebrim Front to learn more.
Requirements
This quest is available if you have completed the quest Heretical Harassment.
Starting the Quest
Talk to Haurchefant in Camp Dragonhead in the Coerthas Central Highlands to begin the quest. There will be a cutscene. This one is important, so it is recommended to watch it either now or via the Unending Journey in an inn room.
Speak with Drillemont
Leave the building and go west to where the orange arrow is pointing in the minimap. Enter the building south of the fire pit, then go up the stairs to find Drillemont. Talk to Drillemont to proceed.
Speak with the Mistreated Merchant
Go down the stairs and leave the building. Go north up the stairs and go through the door on the right, then go up the stairs to the second floor and talk to the Mistreated Merchant to proceed.
Search the Wilds of Snowcloak
Go down the stairs and leave the building. Go southwest to where the orange arrow is pointing in the minimap. Dismount and enter the purple circle. Defeat the Loyal Heretic who is wielding a staff, then defeat the Loyal Heretic who is wielding a lance.
Speak with the House Durendaire Knight
Go west to where the orange arrow is pointing in the minimap. Talk to the House Durendaire Knight. There will be a cutscene.
Speak Once More to the House Durendaire Knight
Talk to the House Durendaire Knight to proceed.
Speak with Drillemont Again
Go northeast to where the orange arrow is pointing in the minimap. Enter the building south of the fire pit and go up the stairs to find Drillemont. (Or you can fly in from the top of the tower.) Talk to Drillemont to proceed.
Speak with Haurchefant
Go up the stairs to reach the top of the tower. Fly east to where the orange arrow is pointing in the minimap. Enter the building and talk to Haurchefant to proceed. There will be a cutscene.
Speak with Slafborn at Revenant's Toll
Exit the building and fly southwest to reach Mor Dhona. Talk to Slafborn near the Mor Dhona aetheryte to complete the quest.
Next Main Scenario Quest
After you complete the quest, talk to Slafborn to accept the next quest: Brave New Companions.