"The alien is an all-consuming destroyer, a whisperer of tempting lies that wishes to dominate and subjugate mankind utterly -- such dull platitudes are those of the dutiful simpleton. The truth is worse by far."

Inquisitor Augustine Mordecai, address to the Hilician Symposium
Inquisition Logo

Symbol of the Inquisition.

The strange and sinister xenos race known to the Inquisition as the Cryptos comes from the cold darkness of the interstellar void where it can scarcely be conceived that anything could live. Without solid physical form, they appear as strange gaseous clouds tinted with an eerie greenish glow and filled with maddening, half-formed shapes. They are able to pass through solid matter and even through the hulls of star vessels, and far more dangerously, they have the power to take living human bodies as hosts in order to fulfil their inscrutable aims.

The Cryptos are a cold and mysterious species whose desires and thoughts remain hidden from others and possess an implacable and patient intelligence. Masked in human flesh, they walk amongst Mankind and secretly infest communities, twisting them until they are completely under their dominion.

They treat humans with utter disdain and a callous disregard, for these seemingly immortal creatures carry themselves as fallen gods fleeing something greater and more terrible yet, and Mankind is to them no more than cattle to be used and disposed of at will. The Cryptos are a rare and utterly insidious threat, and though no cities have burned in their name nor have they raised armies against the dominion of the God-Emperor, they are the manifestation of why the alien is loathed and mistrusted in all of its forms by the Imperium of Man.


How long the Cryptos have existed is completely unknown, but what can be guessed at is when the Cryptos first began to infiltrate Mankind. This moment can only have taken place during the ages in which man has moved amongst the stars, as the remote existence of the Cryptos beyond the warmth of suns would have kept them away from the planet-bound beginnings of humanity.

Dwelling in the lightless margins of star systems or in the deep void, the Cryptos must have met with Humanity and learned its weaknesses, its flesh-bound desires, its fears, and its ignorance. They must have seen a possibility in the fleshy race they could so easily possess, the possibility of domination and concealment, because for all their utterly alien nature the Cryptos have one thing that can at least be approximated to a human emotion -- fear.

The unknown object of their fear may even have driven the Cryptos into their bodiless existence, hiding in the emptiness, perhaps drifting away from some ancient enemy or star now long dead. However, it seems to them that the human Imperium represents their greatest chance of successfully hiding from whatever it is they flee.

How long ago the process of infiltration and control began and how many Cryptos there are in the Imperium today can not be estimated with any accuracy. However, infestations have been uncovered on scattered Imperial worlds in the Segmentum Obscurus and Segmentum Pacificus ever since this alien species was formally identified and confirmed as "Diabolous" in the 35th Millennium. It has been noted by some in the Ordo Xenos that the number of instances of Cryptos infestation may extend far further into the past, but such instances may have been mistakenly treated as instances of witchery or daemonic influence.

The Incident at Fall Narrow

The Calixis Sector has had only a single, formally-identified instance of a Cryptos infiltration being discovered and destroyed since its foundation, although several more are suspected. This single verified infestation occurred at the mining community of Fall Narrow on 88 Tanstar nearly two Terran centuries ago in the seventh century of the 41st Millennium.

Numbering under a thousand inhabitants, the settlement of Fall Narrow was relatively efficient and quite unremarkable; it met its quotas, people were born, worked, and died without unusual incident, and various officials passing through did not find any cause for concern. So things might have continued were it not for a mining accident that was witnessed by a travelling Administratum scribe detailed to carry out a local census.

Dozens died during this mishap, and the scribe, to his horror, saw the settlement overseer impaled by a fallen joist. As he died, the overseer's body thrashed about and a green cloud billowed out of his eyes and mouth. The scribe recorded the unwholesome sight on his ocular augmetic before fleeing. In response, the panicking regional governor deployed Enforcer units that attempted to storm the settlement and conduct an investigation.

The assault turned into a massacre as the ordinary men and women of the settlement resisted fiercely. The violence quickly and dramatically escalated with the miners attacking the Enforcers with makeshift demolition charges and industrial machines and the Enforcers responding with heavy assault units (the locals seemed to be under the delusion that they were being attacked by corsairs and outlaws).

Captured prisoners showed signs of psychic suggestion and mental tampering, and it was clear something alien and malign was at work. This became particularly evident when the Enforcers' own encoded Vox-net was compromised and an entire strike force was led into a trap and destroyed.

At some point during the assault, the central explosives store detonated, (although whether deliberately or by a stray round remains unknown). In the explosions and fires that followed, the settlement and almost all of its inhabitants and many of its besiegers were killed.

When the Inquisition arrived shortly afterwards, it found that in a demonstration of either compounded incompetence or xenos conspiracy no records were kept of surviving inhabitants (if any) or the names of surviving Enforcers involved in the incident. Given the ability of the Cryptos to possess victims, their evident intelligence, and their skill at evasion, the xenos threat was likely merely displaced to another quiet and unassuming backwater. Despite a full Inquisitorial investigation, no further trace of the Cryptos colony was ever found.

Anatomy and Physiology

The Cryptos exist physically as an etheric, pseudo-plasmic, gas-like substance bound by an esoteric energy field that to the human eye appears as a hazy cloud of green-tinted vapour. In their natural state, the Cryptos drift in the great dark voids of the galaxy in small groups who commune via psychic means and are (unless destroyed by violence) effectively immortal.

Usually these drifting groups are small, rarely numbering more than a dozen. The utterly alien preoccupations of the Cryptos prior to their contact with Mankind are not open to human understanding. Born in the deep void between star systems, they do not possess intelligence or emotions as humans understand them. However, they know and understand the human mind with an alien objectiveness gleaned from the minds of those they have possessed over the years.

The Motivations and Infiltrations of the Cryptos

The Cryptos dominate and control humans, using them with a callousness that is as cold as the void from whence they came. They have no lust for dominion over the weak and fleshy realm of Mankind; instead their infiltration of human communities offers them protection. None can guess at the terror from which they flee and perhaps even they can no longer recall its nature (except for a crawling dread embedded in their racial memory), but to this end secrecy and security are their overriding goals.

Regardless of the cause of their fear, the fundamental motivation of the Cryptos has remained unknown to the Inquisition, though some subtle-minded savants serving more Radical masters within the Inquisition have begun to conjecture along the correct lines. Once they have taken human hosts, the Cryptos need to guard against Humanity itself and keep their presence utterly secret, as they know full well the lengths that the Inquisition will go to in order to root them out if discovered.

Simply appearing to be the people they have taken as hosts does not suffice, and though they can mimic the knowledge, reactions and personalities of their hosts to an almost perfect degree, their need for safety drives them to build sanctuaries in isolated corners of human society for their long-term protection.

The Cryptos are not a numerous species and operate in small groups ranging from a handful to perhaps as many as 20 individuals. When taking hosts, they seek to migrate to obscure and overlooked locations where any side effects of their infiltration will be easiest to control and where they can exert influence over normal humans by taking influential members of the community as hosts.

Overseers, preachers, merchants and those in official positions are usually those taken by the Cryptos in the first stage of infiltration, as they are the keys to dominating the humans around them. Thus the Cryptos make their sanctuary more secure and their presence more difficult to detect. Small, self-contained communities are ideal for their purpose, particularly if physically isolated, although they have a distinct aversion to very primitive societies and dislike operating in space aboard vessels longer than they have to.

After finding and infiltrating such a location, the Cryptos may migrate from body to body several times, leaving dead or damaged hosts along the way. They may spend several human generations acting as covert rulers and conducting culls to weed out any potential dissent or threat to them, before moving on once more if endangered or due to the urgings of their own inscrutable time table.

While they are in control, the Cryptos will attempt to make the communities they hide in as stable and secure as possible so that no undue attention is directed towards them. Over time, the Cryptos are able to seed a psychic influence over those who are close to them. This influence gradually builds until the humans who have ignorantly dwelt with the Cryptos can be made to obey almost any command.

This controlling effect is no literal puppetry but rather a power of suggestion that the Cryptos can wield to deadly effect in their defence or to carry out their wishes. The Cryptos also use the human predilection for hierarchy and authority to further secure their control by creating guilds and fraternities that gradually become more and more important to the community that they are part of. The control of such organisations extends and crystallises the Cryptos' dominion of their "sanctuary community" and allows them to create a network of spies and servants to enact their will.

Such secretly dominated communities can exist for generations with the Cryptos passing to suitable new hosts when the flesh of the previous ones fail. Should their carefully constructed sanctuary be threatened or draw Inquisitional attention, the Cryptos will move to eliminate the threat using all available resources and then, once the threat has been eliminated, restore their human community to its "normal" state as if the threat had never existed.

Knowledge and Ignorance

Little is known of the Cryptos, and what is known is often confused with information about other alien speces. Presented here are guidelines on what different groups know about the Cryptos and their activities outside of academia and Imperial history.

  • The Void Born and Ship Dwellers - There are many Void Born myths that relate to unexplained incidents and strange phenomena that may have the Cryptos as their true source. Particular references to small ships going missing only to be later discovered lifeless, deactivated, and sometimes concealed within asteroid belts and gas giants in outlying colony systems may have something to do with the Cryptos' activities. Likewise, tales of "ghost lights" haunting voidships when visiting distant and empty star systems or crewmen acting in an uncharacteristic manner may perhaps relate to the Cryptos.
  • Ordo Xenos - The race has been declared Xenos Diabolus by the Inquisition and is to be destroyed whenever found. Various factions within the Ordo Xenos have differing ideas as to the severity and danger of the threat. Some Radicals even believe that some effort should be made to capture and preserve a specimen to unlock its potentially ageless knowledge.

Ordo Xenos Departmento Analyticus Threat Briefing

Within the Calixis Sector, the current threat posed by the Cryptos is unknown. There have been no recent indications of a hidden infestation and no reports that an infestation might exist. On such evidence, there can be only one conclusion by the Ordo Xenos: the threat is most severe.

The few instances of Cryptos activity within the sector indicates that this region of space is not unknown to them. Silence can only mean that out amongst the scattered worlds of the sector there lurk what seem to be men and women, who work, talk, and eat, blending in with their fellows, but inside them is nothing but a cold intelligence, born of the void and driven by terror to escape from something even worse.


  • Dark Heresy: Disciples of the Dark Gods (RPG), pp. 91-94
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