Chaos Cults are the most dangerous of all those organisations that plot to overthrow the rule of the Imperium of Man from within. All planets and civilisations belonging to the Imperium can harbour Chaotic organisations, which themselves are as diverse in practice and membership as is imaginable. From the blood-soaked sacrificial cults of Feral Worlds to the philosophical secret societies of more advanced planets, the temptations of Chaos can capture all. The objective of the Chaos Cult is to survive and eventually dominate the society in which it dwells. Mere survival is particularly important on Imperial worlds, where Chaos worship is the greatest of heresies and Inquisitors are always vigilant and ready to wipe out any taint of Chaos. Generally clandestine in nature, as discovery could bring with it attention from the local Adeptus Arbites contingent all the way up to the Inquisition, cults often hide behind the front of some form of legitimate Imperial organisation in their attempt to accumulate local or planetary power, such as trade unions, charitable organisations, accepted religious groups and even local variants of the Imperial Cult. Extreme political parties make good fronts for cults, as they naturally attract power-hungry and mentally unbalanced individuals, who make particularly good material for potential cult members. A very successful organisation can achieve real political power, even gaining enough power to make it possible for the cult to become the governing body of the planet without having to resort to outright rebellion.
After taking root, and as it expands in power and influence, eventually the cult may end up effectively ruling anything from a township to the entire planet. Eventually, an uprising breaks out, either purposefully or because the cult has grown too large and/or unruly to remain secret any longer. At this point, the cult can be expected to summon aid from their Chaotic masters, ranging from daemonic possessions of cult members to the outright summoning of Traitor Legions through the Warp to the planet. Cults may also unleash an uprising in concert with a pre-planned invasion of Chaos Space Marines. The ultimate aim of the cult's uprising is to overthrow the Imperial government and attain direct control over the world. After the conflict, cultists are often taken back into the Eye of Terror where they either join the damned population of a Daemon World or are recruited (sometimes forcibly) into a Chaos Champion's armed forces.
Notable Chaos Cults
The Blood Pact is a Chaos warband devoted to Khorne, differing from other such war bands in that they follow an unusually disciplined way of life. They can be found in the Sabbat Worlds Sector, primarily around the world of Ghourra. Unlike many Chaos Cultist warbands, the Pact fights as a disciplined army against the onslaught of the Imperial Guard's Sabbat Worlds Crusade, and this is what makes them so effective compared to the usual disorganized Chaotic masses. Consisting of highly trained, vicious soldiers and xenos mercenaries, the soldiers of the Blood Pact know no fear or hesitation. They have overrun entire worlds and caused the people of the Imperium no small amount of suffering and woe.
The Carnibales are an insurgency native to the planet Solo-Baston which began when the Ecclesiarchy began appropriating land from the indigenous population. When the Ecclesiarchy, the ruling power on the shrine world of Solo-Baston, began appropriating the lands of the various tribes to turn over to agricultural use what first appeared to be a grass roots insurgency began to trouble the planet. In reality the rebellion was instigated by the Dos Pares, members of the Blood Gorgons Chaos Space Marines. The Carnibales were able to very quickly massacre the Solo-Baston Planetary Defence Force (PDF) who had not expected the insurgency. Eventually the Imperial Guard was called in to put down the rebellion, however their efforts proved futile because the carnibales had captured the super heavy Earthwrecker siege gun, which allowed them to thwart any attempt to land on the main Solo-Baston landmass. Though initially none of the Imperial authorities suspected the insurgency was aided by the forces of Chaos the increasing number of mutants among the Carnibales fighters and the growing number of shrines to the Dark Gods made this fact blatantly obvious.
Children of the Merciful Lord
The Children of the Merciful Lord were a Chaos Cult responsible for the war with the Imperium on the world of Cordassa.
Children of Sanguinary Unholiness
The Children of Sanguinary Unholiness was a massive Chaos Cult of Khornate Berserkers dedicated to the service of the Blood God Khorne which joined the Daemon Primarch Angron and his World Eaters Traitor Legion aboard the Space Hulk Devourer of Stars to launch an invasion of the Hive World of Armageddon in the Segmentum Solar in 444.M41. These cultists were drawn from the population of the Daemon World controlled by Angron and the World Eaters within the Eye of Terror and they were used to supplement the forces of daemons and Chaos Space Marines that Angron used to launch what would become known as the First War for Armageddon. The Children of Sanguinary Unholiness numbered in the millions but were ultimately defeated through the actions of Armageddon's mortal defenders amongst the Imperial Guard and its Planetary Defence Forces and the assistance of the Space Wolves and Grey Knights Space Marine Chapters.
The Infardi were Chaos Cultists native to the planet Hagia in the Sabbat Worlds Sector. They took their name from a local word for pilgrim and wore robes of emerald green which mocked that shrine world's Imperial faith. They were tattooed with images of Saint Sabbat in congress with daemons and Chaotic runes. They were led on Hagia by their general Pater Sin. It is presumed that the Infardi were destroyed upon activation of the psychic amplification device beneath the Shrinehold of Saint Sabbat, save for Pater Sin, who had fled Hagia some days before. Infardi is also the Hagian name for pilgrims of Saint Sabbat.
The Ironclad are a large movement of Chaos pirate raiders active in the Medina Corridor who are also dedicated to the service of the Ruinous Powers and the spread of their faith.
The Lost and the Damned
The Lost and the Damned include the hordes of Chaos Cultists that follow Abaddon the Despoiler during the Black Crusades of Chaos Undivided. Also in use as a more generic term for all of the human or mutant forces of Chaos that are not Chaos Space Marines.
The Serpent Lodge was the name given to both a group of suspected Chaos Cultists and their Temple on the planet of Davin. The Lodge members treated the Warmaster Horus at the direction of the Word Bearers' Chaplain Erebus for the crippling injury he received campaigning on Davin's moon, and the Lodge itself is the location where Horus is believed to have begun his alignment with the Chaos Gods.
The Shriven were once workers on the Forge World of Fortis Binary, however they were corrupted by the temptations of Chaos. They were described as elephantine, with long, nozzled gas masks sewn into their faces. They wore rubberised green body armour and the protective garb of their former workplace. Their armour was decorated with eye-aching runic symbols of Chaos.
Sons of Sek
The Sons of Sek are a Chaos warband, structured upon the Blood Pact and loyal to Magister Anakwanar Sek. Like the Blood Pact, the Sons of Sek are similar in structure to the Imperial Guard, with the Sons of Sek even including an equivalent to the role of an Imperial Commissar, which the Blood Pact do not. Their eventual purpose is to lead a coup against the forces of Archon Urlock Gaur, giving Sek command of all the Chaos forces in the Sabbat Worlds. The Sons of Sek were primarily formed and trained on the Chaos-held world of Gereon, until the reconquest of that world by Imperial forces as part of the Sabbat Worlds Crusade.
The Stigmartus are a Chaos Cult and warband operating in the Jericho Reach. They were key components of those Forces of Chaos who stood against the Imperium's assault upon the region in the Achilus Crusade. Consisting of Renegades, madmen, Imperial criminals, cultists, mutants, and rogue psykers, the Stigmartus was named for the ritual branding of its members' flesh with the sigil of their Chaotic masters. Although they are brutal and frenzied to the extreme, like the Blood Pact they maintain harsh discipline and military-style professionalism, and are organised along the lines of an Imperial Guard regiment. The commanders of the cult are believed to be the remainder of the previous Heretic rulers of the world of Khazant, which fell to the Imperium during the early years of the Achilus Crusade. Now Stigmartus are bound to the charismatic leadership of a cult-general known as Elak Sarda, who is said to be sworn to the service of a daemonic entity within the Charon Stars.
Vraksian Traitor Militia
The Vraksian Traitor Militia were a motley assortment of Planetary Defence Force troopers, garrisoned Imperial Guard auxilia from the planet Vraks, indentured Departmento Munitorum Labour Corpsmen, the Ecclesiarchy's Frateris Militia, and local volunteer soldiers, who rebelled against the Imperium whilst under the sway of the heretic Apostate Cardinal Xaphan. After the previous Cardinal of the Scarus Sector in Segmentum Obscurus died, his successor, Cardinal Xaphan, took his place as the Cardinal of the Scarus Sector. Over the course of many years, Xaphan undertook a pilgrimage across the Scarus Sector, his new domain. He wished to see the places he would preside over, and he wished to bring a spiritual revival to the people. Where he and his entourage passed, he amassed ever more followers in a series of religious uprisings. Criminal governments and oppressive tyrannies were shattered with each world he traveled to. Whispering into his ear was the Cardinal's favored advisor, Deacon Mamon, a secret devotee of Chaos. After years of pilgrimage, Xaphan went into seclusion on the Imperial Armoury World of Vraks Prime, also the site of a popular Imperial Cult shrine. Here, Xaphan chose his battlefield. Believing that corruption was eating away at the Imperium, he thought himself a messianic figure destined to ignite a holy war and give the faithful a chance to purge the galaxy of darkness. Believing the Cardinal to be amassing far too much popularity and power, an agent of the Officio Assassinorum was sent by the Ordo Hereticus of the Inquisition to assassinate Xaphan during one of his sermons. After the failed attempt on his life by this operative, the Armoury World of Vraks erupted in full-scale rebellion against the Imperium. It wasn't long until the Citadel and the industry of the armoury world were under Xaphan's control. By seceding Vraks from the Imperium, Imperial forces in the sector and, in some cases, the entire Segmentum, would be left without adequate resupply of arms and armour. By breaking the Imperial supply chain of which Vraks was a part, forces as far removed and important as the Cadian Imperial Guard regiments guarding the Eye of Terror would be sparsely armed, allowing a potentially major Chaos incursion to occur in or around the Cadian Gate. The Administratum deemed that Vraks must be returned to the Imperium's fold. By the time word reached the Imperium of the rebellion on Vraks, it was already too late. Millions of Traitors and heretics were now dug into meticulously planned, constructed, and reinforced defences, with massive orbital lasers protecting the world's Citadel from orbital bombardment and assault. It fell on the Imperial Guardsmen of the Death Korps of Krieg, united under the umbrella of the Imperium's 88th Siege Army, to dislodge the traitorous forces of Cardinal Xaphan in what would become a grinding war of attrition that would consume millions of lives across 17 standard years of battle and would enter Imperial records as the Siege of Vraks.
- Chapter Approved 2001
- Gaunt's Ghosts Novel Series
- Horus Heresy Novel Series
- Codex: Eye of Terror
- Imperial Armour Volume Five - The Siege of Vraks - Part One
- Realm of Chaos: The Lost and the Damned, pp. 168–172
- Flesh and Iron (Novel) by Henry Zou
- Emperor's Mercy (Novel) by Henry Zou
- Deathwatch: Core Rulebook (RPG), pg. 348
- Deathwatch: Achilus Assault (RPG), pg. 69