The Harrowing was a Chaos Space Marine warband in the early years of the 33rd Millennium. It was led by the warlord Gzrel and a coterie of Chaos Sorcerers comprised of Maroth, Xiatsis, Cottadaron and one called Horkos, who was apparently the weakest and most subservient to Gzrel and Maroth.
On the edges of the Eye of Terror, the Harrowing encountered an undermanned rogue Adeptus Mechanicus vessel, the Titan Child, commanded by the Tech-priest Carmenta. Thirty Harrowing Heretic Astartes boarded the Titan Child and encountered four Loyalist Astartes -- Thidius, Cadar, Kadin and their leader, a Librarian called Astraos.
Cadar was nearly killed and after the battle his body was transformed into a Daemonhost by Maroth. The other three were incapacitated, and so Maroth took an eye from each of them.
The Titan Child was then captured and refitted with a makeshift throne room in order to serve as a flagship for Gzrel. Carmenta was enslaved and the other slaves aboard were sacrificed to the glory of Chaos as the vessel was quickly corrupted by the Ruinous Powers.
Shortly after capturing the Titan Child, however, a warship of unknown provenance, known as the Blood Crescent, approached. From it came a sorcerer, Tolbek, an exile of the Thousand Sons, accompanied by a pair of Rubricae. Tolbek claimed he sought the former First Captain and Librarian of the XIV Legion, Ahzek Ahriman, whom he believed was hiding within the Harrowing.
In Gzrel's throne room he looked at each sorcerer and realised that the meek, beak-helmed Horkos was in actuality Ahriman, and after psychically communicating with the wayward First Captain, he immediately attacked. In the ensuing battle, Tolbek, Gzrel, Xiatsis and Cottadaron were killed, and Maroth's mind was shattered.
Afterwards, Ahriman sought out Carmenta, mistress of the Titan Child and freed her. He also freed Astraos and his two living brothers, earning their fealty. Together, the five killed all of the Harrowing Chaos Space Marines aboard the Titan Child and initiated a battle between Tolbek's unassuming vessel and the Blood Crescent, damaging both vessels and allowing the freed Titan Child to escape with Ahirman and his group.
The remaining Harrowing were left aboard on the severely damaged and listing Blood Crescent. Their eventual fate is currently unknown.
The Harrowing warband's colours are not listed in current Imperial records.
The Harrowing warband's iconography is not listed in current Imperial records, but they wore the usual Chaos fetishes and iconography, showing their allegiance to the Ruinous Powers.
- Ahriman: Exile (Novel) by John French