The Black Brethren of Ayreas are a warband of Chaos Space Marines drawn from the Black Legion who follow the Chaos Champion Ayreas. They were among the Forces of Chaos and the 11 warbands and Renegade Chapters of Chaos Space Marines who participated in the the infamous Siege of Vraks (813-830.M41).
- Siege of Vraks (813-830.M41) - The Black Brethren of Ayreas were one of the 11 warbands of Chaos Space Marines who heeded the Alpha Legion Chaos Lord Arkos the Faithless' call to the Imperial Armoury World of Vraks Prime to take part in the slaughter and mayhem that marked the 17-year-long siege by Imperial forces.
The Brethren of Ayreas wear predominately black Power Armour with gold trim. Like many different Chaos warbands and companies, many warriors of this particular warband choose to adopt individual schemes and iconography on their armour.
- Imperial Armour Volume Seven - The Siege of Vraks - Part Three
- Imperial Armour Volume Thirteen - War Machines of the Lost and the Damned, pg. 43