The Bilious Ones are a warband or vectorium of the Death Guard Traitor Legion's 4th Plague Company. They are commanded by a Death Guard Sorcerer and are one of the few Death Guard warbands which likes to enter battle amidst living carpets of Nurglings, the Lesser Daemons of the Plague God Nurgle. Little else is known about the Bilious Ones in current Imperial records.
The Bilious Ones' Power Armour is the same as that of the Death Guard, composed of decayed and cracked plates of ceramite discoloured in sickly greens and browns. Bilious Ones Chaos Space Marines, like those of the Death Guard, often wear grotesquely warped suits of the antique Mark III Iron Pattern of Power Armour.
The Bilious Ones' warband badge is usually a modified version of the standard Mark of Nurgle, similar to that used by the rest of the Death Guard.
- Codex Heretic Astartes - Death Guard (8th Edition), pg. 53