The Cult Assassin is a member of the an unnamed cult that worship's Aec'Letec. Two are encountered with the first group of cultists that greet you when you the first time you arrive in Ulgoth's Beard with the Soultaker Dagger in your inventory. There are two more with the second group of cultist waiting inside Shandalar's Home. They are initially invisible and deal significant backstab damage.
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