The Brotherhood of Darkness are a warband of Chaos Space Marines of unknown origin and allegiance, though they may be related to the Night Lords Traitor Legion, due to their their similar iconography.
- Quabbalis Heresy (Unknown Date.M40) - The Brotherhood of Darkness are known to have taken part in the Quabbalis Heresy.
- Acteron Sector Ambush (003.998.M41) - In another incident the Brotherhood of Darkness are known to have ambushed an Imperial convoy consisting of cargo vessels, transports and civilian passenger starships in the Acteron Sector in 003.998.M41. The convoy was completely destroyed and there were no Imperial survivors.
The Brotherhood of Darkness wear jet-black Power Armour with red trim on the shoulder guards. The armour is covered in yellow glowing blasphemous glyphs.
The badge of the Brotherhood of Darkness is a bone-coloured, horned skull with crimson bat-like wings on a black background, strikingly similar to that of the Night Lords Traitor Legion.
- Battle Missions (2010), pg. 9
- Codex: Chaos Space Marines (4th Edition), pg. 18