Arval was a servant of the King of Shadows. He was sent to Neverwinter to form a secret cult and attract the younger citizens to join the cult. Once he gathered enough followers, he prepared the ritual to join with the shadow.
When the Kalach-Cha came to the end of the Bryce crypt, Arval would be about to finish the ritual. He and his followers would attack the Kalach-Cha. However, Lisbet Bryce then completed the ritual, causing Arval and his followers to be revived as shadows, who would attack once more.