Merlin LaRoth

Merlin LaRoth was an alchemist/necromancer in the city of Grindwall. He was responsible for the development of the werewolf plague in Grindwall's Lower Residential District/Quarantine District because he was trying to replicate lycanthropy without it being magical.
When the party found him, he was in his mansion and had become a wraith. The party destroyed the wraith version of him. 
It was implied that he was working with The Grasp.