You will now need to find 4 symbols They are located at:
Kill Dvith N'Zur (Symbol of Trev). You have to get him to spawn. Go down to the bottom of the falls where you killed the underwater goblin from the previous quest. You must kill all the vampires down here. Then you will spawn Dvith and 4 or 5 nightmare of Dvith (look like wisps). Kill the nightmares then Dvith becomes attackable. 52, -41, 98
Examine coffin in the large room (where you were for other quests, -83, -22, -62 . This will give you Symbol of Veth.
Kill Rhayn T'Dax (Symbol of Raet). Named along with 4 seers near drained grinnin in the tunnel. He can be found at 51, -22, -100 in the tunnel between the first and second levels.