Louis Cypher

A Bretonnian Necrarch, Louis Cypher sought to increase his magical abilities by absorbing the stored power of the ancient standing stones that are scattered over the Old World. With each stone he uprooted, his power grew, as did his legion of the damned. Some say those stones were erected by the Elves before their war with the Dwarfs, and Louis Cypher evidently believed this because he took his army aboard a fleet of ghostly ships and sailed to the land of Ulthuan. He has not been heard of since, and whether he was eradicated by the High Elves or if he fights them still for the magic locked into their network of standing stones, none can say.

Source

 * Warhammer Fantasy RPG 2nd ED -- Night's Dark Masters (pg. 62).