I returned and told the Pale Tree about the creature I saw. Trahearne believes it is a lich called Mazdak the Accursed. Mazdak was involved in the death of Firstborn Riannoc, the first sylvari to die. The Pale Tree had given Riannoc a magic sword formed from her own thorns, but with Riannoc's disappearance, the sword has never been found. The Pale Tree has asked me to recover the sword, Caladbolg, and find out what happened to Riannoc.