Sisters of Silence art

The Sisters of Silence were the most notable Blanks employed by the Imperium of Man during the Horus Heresy

A psychic Blank, also known as an Untouchable and a Pariah, is a human who possesses the rare Pariah Gene that makes them generate no presence in the Warp, thus leaving them essentially soulless. Known also as "Blacksouls", "Psychic Nulls" and "the Souless", a Blank is a living anathema for all psykers, regardless of species. A Blank is the direct antithesis of the force of Chaos as he or she possesses no presence within the Warp, and thus radiates a sense of unnatural "wrongness" that makes other living, intelligent creatures extremely uncomfortable and uneasy in their presence. A Blank's proximity to someone who possess even a modicum of psychic ability can be quite painful or even lethal, especially to extremely psychically sensitive beings such as the Eldar. It is currently believed by the Adeptus Mechanicus that the Pariah Gene was deliberately engineered into the genomes of the ancestors of Mankind by the Necrons millions of standard years ago during the War in Heaven. Blanks today are most often used by the Officio Assassinorum's Culexus Temple and as Acolytes by Inquisitors of the Ordo Hereticus who find them to be useful shields and weapons against the witch and unsanctioned psykers. On the Psyker Scale commonly employed by the Adeptus Astra Telepathica, Blanks occupy the nethermost levels, from Phi-plus to the extraordinarily rare Omega-minus level.


An Untouchable is non-psychic, for they bear the Pariah Gene, which severs the bearer's mind completely from the Warp, effectively making them both soulless and immune to all forms of psychic assault. Their minds are also unreadable by any known means of telepathy. The bearers of the Pariah Gene possess the innate ability to disrupt psychic abilities -- they are "perceived" by psykers as a completely unnatural "hole" in the reality of the Immaterium. Their mere presence is thus intolerable to a psyker. Even in humans and aliens categorised as Level Sigma and below in psychic ability, Blanks cause unbidden discomfort and hostility. Close proximity or intimate contact with a Blank can cause a psyker excruciating pain. The Soulless are very rare in the galaxy since perhaps only one person on an entire world will be a carrier of the gene in every human generation. There are no known instances of Blanks existing amongst the nonhuman races of the galaxy. Pariahs are often used by the Inquisition and the Ordo Hereticus against witches and Renegade psykers. Also, due to their soullessness, human Pariahs are completely without fear. However, most Pariahs do not live long as the feelings of hatred and distaste they generate among even non-psychic individuals means they have few friends and many enemies.

The most well-known examples of the use of Blanks by the Imperium of Man was the existence of the mysterious all-female order of Witch Hunters known as the Sisters of Silence. During the Great Crusade era in the early 31st Millennium, their purpose was to hunt and kill rogue human psykers whose activities presented a terrible danger to the people of the newborn Imperium. Also known as the Silent Sisterhood and the Witchseekers, they were the militant arm of the Adeptus Astra Telepathica and were referred to internally within the records of the Council of Terra (predecessor to the Adeptus Terra and the Senatorum Imperialis) as the Departmento Investigates. The ultimate fate of the Sisters of Silence is not found in Imperial records, and no references to their continued existence in the era of the 41st Millennium exists. It is believed that they were either destroyed long ago or were ultimately folded into the organisation of the Imperial Inquisition. The Sisters of Silence's primary base of operations was the Somnus Citadel on Luna, the moon of Terra.

These warrior-investigators were tasked with the apprehension of untrained psykers, often colloquially referred to on primitive human worlds as "witches," whose abilities sometimes manifested in ways that could be very dangerous to their fellow human beings, particularly if they became hosts for the foul entities of the Warp. The Sisters operated the Adeptus Astra Telepathica’s infamous Black Ships, which ranged the galaxy following behind the Great Crusade's Expeditionary Fleets in search of rogue psykers to capture or expunge, seeking to collect and carry them back to Terra where they would be tested and their eventual fate decided. Though few in number, the Sisters of Silence commanded great respect within the Imperium and most servants of the Emperor regarded them with some awe. Few would willingly stand in their way or interfere with their activities and few indeed were those who were comfortable in their presence. It is hardly surprising that Blanks are often treated like outcasts or lepers in Imperial society, rejected by their parents and banished from their homeworld's local settlements. Local superstitions on many worlds often warn about touching them, saying that to do so would bring bad luck. Resigned to their fate, many Blanks lead simple, solitary existences, as far away from heavily populated areas as possible.

Another well known instance of Untouchables used by the Imperium are the Culexus Assassins of the Officio Assassinorum's Culexus Temple. The Assassins of this temple have been described by Eldar Warlocks as being nothing short of the embodiment of pure evil. Even amongst the upper echelons of the Officio Assassinorum this temple is always viewed with extreme caution. The reason for this is not because of the way that the Culexus Assassins carry out their operations, or the heinous methods of killing they employ. It is because of the very nature of the Culexus Assassins themselves. This extremely rare genetic defect occurs for no known reason in less than one in a billion individuals. However, in recent years evidence has emerged that the Pariah Gene was engineered into Mankind's ancestors million of years ago by the C'tan and their Necron servants so that humanity might be used as a weapon against the psychic species like the Eldar and the Orks that the Old Ones had created to defeat the C'tan. It is for this reason that the Necrons capture human Blanks with the Pariah Gene and transform them into the hideous Necron Pariahs. All psykers and intrinsically psychic species like the Eldar consider a being like a Culexus Assassin to be an absolute abomination. Even monstrosities such as a Tyranid Hive Tyrant can balk at the prospect of being permanently severed from their psychic abilities and the Hive Mind. The Culexus Assassin causes absolute terror in all psykers -- which is why they are so useful to the Imperium.

Great Crusade Era


A Culexus Temple Assassin utilises the Animus Speculum to slay his foes

When the Sisters of Silence first captured and transported large numbers of Untouchables back to Terra during the Great Crusade, humanity had its first disturbing revelation of the potency of these strange mutants. As large groups of Pariahs were brought to Terra, they began to cast a shadow in the Warp, blocking out the Astronomican, the vital psychic beacon used to guide starships to the far reaches of the Imperium.

Other branches within the Imperium of Man, especially those that relied upon the abilities of psykers, were horrified by the existence of Pariahs. Several members of the Council of Terra sought to have Pariahs outlawed outright like other dangerous mutants -- tasking the Sisters of Silence with the ruthless extermination of any more Blanks that were found just as they eliminated Renegade psykers who presented a threat to humanity. A number of members of the Council of Terra, including the Paternal Envoy of the Navis Nobilite, were pushing the Emperor of Mankind to issue an official decree to rid the Imperium of the "anti-psyker" mutants that threatened their Adeptas' very existence.

This was unfortunate, for the Officio Assassinorum had been working in secret with the Magos Biologis and Genetors of the Adeptus Mechanicus on the order of Malcador the Sigillite, the Regent of Terra and the founder of the Officio as the first Grand Master of Assassins, to see if it was possible to harness the Blanks' strange abilities and use them to kill psykers. Their work was almost complete; many years had been spent developing specialist wargear and training techniques, all of which was about to be ruined by a zealous political witch-hunt.

Fortunately, the Emperor never had to issue an official decree, for at Malcador the Sigillite's behest, the Adeptus Mechanicus announced that it was ending the Pariah Project, making a great show of closing down its laboratories and executing many of the "specimens" it had tested there. Satisfied that no further action was needed, the bureaucrats of the Council of Terra turned its attention to the more important matters at hand.

However, closer study of the fragmentary Imperial records from this time reveal that the number of executions did not match the number of Pariahs contained within the laboratories of the Mechanicus. Working in collusion with the Officio Assassinorum, the Adeptus Mechanicus spirited away the most promising Pariahs to a specially constructed fortress hidden on Terra, beyond the reach or knowledge of the more zealous branches of what eventually became the Adeptus Terra after the Horus Heresy. It was there that the Culexus Temple, originally known as the Culexus Clade, was born in its modern form under the direction of its first Director Primus, the individual known only as Sire Culexus. Culexus had sworn an oath alongside Malcador and the five other Directors Primus of the newborn Officio Assassinorum to defeat every enemy of the Emperor no matter where or how they sought to hide from Imperial justice. The Blanks of the Culexus Clade would become an important component of keeping that vow.

Notable Untouchables

  • Black Pariah - Within Imperial history, there has only been one known so-called "Black Pariah" to have ever existed. He was a former Imperial Assassin by the name of "Spear," who lived during the time of the Horus Heresy. Born as a human Untouchable, he was captured by the Silent Sisterhood and brought to Terra, where Clade Culexus experimented upon and augmented him in an attempt to create a more powerful and deadly form of Culexus Assassin. It is not known whether these augmentations or his unnatural abilities made him a Black Pariah. Spear was eventually deemed too unstable and dangerous by his Clade's masters to be left alive. He was placed in the care of the Sisters of Silence and was sent aboard one of their lone vessels, bound for the heart of a nearby sun. Unfortunately, this vessel was intercepted by a Renegade vessel carrying the Dark Apostle Erebus of the traitorous Word Bearers Legion. Boarding the Sisters' vessel, the Word Bearers killed all aboard, with the exception of Spear. Sensing the usefulness of such a unique specimen, Erebus found a new purpose for his captive. He forced Spear to undergo a painful and vile Chaotic ritual, in which a minor daemon from the Immaterium was bonded with the former assassin. This bonding created a highly dangerous apex predator -- a "counter-psyker" -- capable of redirecting a psyker's attack directly back upon them. In order to utilise this ability, the Black Pariah first had to obtain a sample of his target's blood. This was a necessary component that helped him synchronise with his target's psionic abilities in order to reflect their attacks. Two standard years later, following the events of the Drop Site Massacre on Istvaan V, Erebus tasked his deadly minion to assassinate the Emperor. Spear spent an inordinate amount of time in order to painstakingly reach his ultimate goal -- a document that possessed a minute drop of the Emperor of Mankind's precious blood. Spear obtained the document on the world of Dagonet, bringing him into direct conflict with an Imperial Execution Force composed of Imperial Assassins from every clade, who were attempting to assassinate the Traitor Primarch Horus. Though the mission was ultimately deemed a failure, resulting in the death of all its members, this confrontation resulted in the Black Pariah's destruction. Horus later chastised Erebus for his audacious plan to assassinate the Emperor, declaring that when the opportune moment finally dawned, it would be him -- and him alone -- who killed the Master of Mankind.
  • Distaff - The Distaff was a group of Blanks created and utilised to hunt rogue psykers by the notorious Inquisitor Gregor Eisenhorn in the 41st Millennium and also seconded by him to other Inquisitors for particular investigations. The leader of this unique group of Untouchables was Alizabeth Bequin. The Distaff proved instrumental in the defeat of the Traitor Inquisitor Quixos, a formally venerated Radical Inquisitor of the Ordo Malleus who became tainted by Chaos. The Distaff was finally destroyed in 386.M41.


  • Codex: Assassins (3rd Edition)
  • Codex: Assassins (2nd Edition)
  • Horus Heresy: Collected Visions (Background Book)
  • Inquisitor Annual Exterminatus Part II
  • Eisenhorn Trilogy (Novel Series) by Dan Abnett
  • Ravenor (Novel Series) by Dan Abnett
  • For The Emperor by Sandy Mitchell,
  • Caves of Ice by Sandy Mitchell,
  • The Traitor's Hand by Sandy Mitchell,
  • Death or Glory by Sandy Mitchell,
  • Ciaphas Cain: Hero of the Imperium by Sandy Mitchell
  • Flight of the Eisenstein (Novel) by James Swallow
  • Thousand Sons (Novel) by Graham McNeill
  • Nemesis (Novel) by James Swallow
  • Prospero Burns (Novel) by Dan Abnett
  • Tales of Heresy (Anthology), "The Voice" by James Swallow
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