I have reduced the ichor you brought me and separated it into its base components.  My findings are not conclusive, but I have determined that warlock and necromantic magics were used in the ichor's creation.$B$BWhile I continue to study the ichor, I want you to take a sample to Bethor Iceshard in the Undercity.  Bethor is not an apothecary, but his knowledge of magic may help to unravel the mystery of the rot hides.$B$BGo.  You will find Bethor in the Magic Quarter of the Undercity.