Kill Kruk'tar the Drunken in Nordland around 18000,42000 for a Mote of Change. Hand in this Mote of Change to Aialye Lynsellia at High elf Chapter 16 in Eataine. Or killing the Soulflame, a level 41 Flamer of Tzeentch. at 48000,7000, you also obtain the Mote of Change.
When you talk to it, the Soulflame says:
Greetings. Your journey to me could not have been an easy one. You seek knowledge and power, I can sense that. You are a worthy sort, I shall share with you knowledge of my kind. Remember well however, that power does not always come so easily.
Title: The Banisher