The Overseer

The band of adventurers encountered The Overseer during their time in Ylil's Domain (Session ?). She oversaw the construction of the portal that would allow Ylil to enter the Material Plane.

Description
A woman attired in golden clothing and jewelry. She was carried at all time on a golden litter manned by several abyssal slaves. Her true name or backstory was never discovered, but the fact that she was humanoid suggests she may have been a possessed member of the Nebrask adventuring party, particularly their spell-caster. Her position may have been achieved through force, as several the other abyssal creatures attempted to kill her to take her position.

Role
The adventuring party used the revolt against the Overseer as a distraction so as to escape from Ylil's slave camp and through the door from which the Overseer arrived, which led to a long hallway cut into the mountain. The ultimate fate of the Overseer is not known but she is assumed dead.