Hotek

A priest of Vaul, Hotek secretly forged weapons for the legions of Nagarythe using the magical Hammer of Vaul, which Caledor Dragontamer had used to make weapons for Aenarion. When he was discovered, Hotek fled and sought sanctuary within Nagarythe. Aided by renegade sorcerers, Hotek used the Hammer of Vaul to construct a suit of armour for the crippled Malekith; although his body had been all but broken, the prince of Nagarythe had clung to life. Bitterness and anger had fuelled Malekith’s will, sustaining him through the long years of agony that he had endured. The burning would never stop, and so Hotek fused his newly forged armour directly to Malekith’s body. Clad in a rune-etched skin of black steel, Malekith could once again lead his armies.

Source
1a: pg. 16 - 25
 * Warhammer Armies: Dark Elves (8th Edition)