Warhammer 40k - Ahriman: Exile by John French

All is dust... Spurned by his former brothers and his father Magnus the Red, Ahriman is a wanderer, a sorcerer of Tzeentch whose actions condemned an entire Legion to an eternity of damnation. Once a vaunted servant of the Thousand Sons, he is now an outcast, a renegade who resides in the Eye of Terror. Ever scheming, he plots his return to power and the destruction of his enemies, an architect of fate and master of the warp.