Khelben Arunsun

Khelben Arunsun is the former Blackstaff of Waterdeep. He currently resides in Phandalin, occasionally serving the king with his magical abilities, under the influence of the Sharingan.

History
Khelben Arunsun was a friend to Lord Dagult Neverember and was given the title of Blackstaff. At some point, the green dragon Muthserash kidnapped his wife, Laeral Silverhand, and kept her hostage in her forest labyrinth. Too weak to fight the dragon himself, Khelben acted out the will of Muthserash in Waterdeep, influencing the political tide in unspecified ways.

Zero Uchiha was able to use the Mangekyou Sharingan to get Muthserash to let Laeral Silverhand go. Still uncertain of Khelben's nature, Zero used his Sharingan on him to insure his obedience to the kingdom and himself.