Abhumans and Mutants
In the Imperium, where doctrine often implies that physical mutation belies spiritual corruption, Abhumans are a rare example of mutants being tolerated by humanity. Many of these are true ‘stable’ divergent subspecies of humanity, often the proven results of evolution to harsh environmental conditions, or genetic tampering. Unlike the spontaneous mutations resulting from toxic materials, or warp exposure, these individuals are often spared extermination, usually because they possess desirable physical traits that makes them useful to the Imperium.
This is not to say they are respected or well treated, Abhumans are still considered subhuman, and are not afforded the full rights of non-divergent humans, their populations are tightly controlled and monitored, their civilizations and access to education are often incredibly restricted, and they never hold status outside their own units when utilized in warfare and indeed often find themselves put under the command of Human officers or Commissars transplanted into their units from outside.
To be an Abhuman in the Imperium is to live a life of being judged and discriminated against. Few humans recognise the difference between mutants and some of the more extreme variations of abhumans, and more often than not ‘sanctioning’ is no protection against Puritan pogroms. An Abhuman will never own a business, be able to fall in love with any being outside their subspecies, or live outside their designated zones, in the military they are barracked far away from other troops, the Imperium often practicing active segregation, and rarely giving abhumans the freedom of leave.
Abhuman Species in the Prosperitas Sector
The Prosperitas sector, distant as it has been from the Imperium for so long, has relatively few native subspecies of humanity, most populations showing such levels of deviance have been exterminated with few notable exceptions. The majority of abhumans currently in the sector are bound to the Prosperitas Crusade, used as cannon fodder for suicide missions where their enhanced brawn is needed, or to one of the Noble Houses as helot workers and servants.
Navigators enjoy a unique position within the Imperium, this subspecies emerged long before the rise of the Imperium and, as a result, were long established in their power bases before the Emperor ascended. The Navigator's unique genetic blessing, the Warp Eye, is an extrasensory perception of the warp that allows them to see the warp and navigate it's dangerous tides, because of the Imperium's dependence on the Warp for faster than light travel, the Navigators continue to be an essential part of Imperial culture, despite their clear genetic deviance. The Navis Nobilite as the Navigator Houses call themselves are twisted inbred lines and often display other variant mutations, inbreeding is an unfortunate side effect of the need of these lines to breed pure, to preserve their unique genetic quirk.
You can read more about Navigators in the Prosperitas sector on their page.
Squats (Homo sapiens rotundus)
The second most accepted/independent abhumans, again because they are largely able to ‘pass’ amongst regular humans, ranging around 4.5 to 5.5 in height with broad and stocky builds. The Squats adapted to live on high-gravity worlds near the galactic core - those small clan enclaves that have made it out as far as the Prosperitas Sector usually display slightly taller than average heights due to freedom from high-gravity situations, but remain broad and stocky. For some inexplicable reason as a result of breeding, Male and Female Squats have greater-than average facial hair growth with males displaying vast beards, while females display large sideburn growths. They are technologically adept, and incredibly good at working in cramped high-gravity mining operations which makes them valuable as helots as well as independent contractors where they are free.
Within the Prosperitas Sector however the Squats are a tiny minority and mostly found in the employ of void-traders. Their technological talents are not tolerated by the Three Forges of the Sector, although there are rumours of Castellum employing these abhumans in junior roles within their assembly-laboratories in order to pursue the Forge's next-wave innovation of ageing Imperial technologies..
Raivans (Homo sapiens furis)
When the Prosperitas Crusade first encountered the Raivans on the freezing eclipse-shrouded desert world of Shadowglow, scouts initially believed them to be cave-dwelling mutants. When later investigation revealed a deep cultural loyalty to the Emperor, ingrained by the use of Shadowglow as a penal world for those who did not swear loyalty to Horus during the Great Heresy, the Imperium soon realized that it was the Raivans and not the ostensibly human Mining Guilds, who were their allies.
Raivans are a proud people, they consider themselves human despite Imperial classification, and often see their mutation as something of a blessing to fight the Emperor's Wars. They are stronger and faster than baseline humans, and have incredibly powerful night sight, even if they do not adapt well to well-lit conditions. They are identifiable by their near-white hair, and eyes that are adapted for night vision, often on well-lit worlds, a Raivan can be identified by their hair and tinted goggles alone. Although still abhumans, Raivan’s are prized as commandos and assassins by various institutions of the Imperium, well adapted as a warrior subspecies as they are, and as a result they often receive a better welcome than more deviant abhumans.
You can read more about Raivans on their page.
Beastmen (Homo sapiens variatus)
An ill-fated species, beastmen as a subspecies teeter on the boundaries of ‘acceptable’ deviance from the human genetic norms. They are a collection of sub-species, often believed to be the result of genetic tampering from the dark age of technology, that seem to represent a fusion of human and animal genetic characteristics. Often a tribal people, because of their extreme deviation they are often treated incredibly poorly, even by the standards of the Imperium’s treatment of abhumans and some puritan factions of the Inquisition endevor to see their kind labeled as mutants and wiped out.
Though some Beastmen in the Prosperitas Sector originated in Auxilia regiments assigned to the Imperial Guard, the majority are the creations of House Vilas-Lobo who breed and adapt them for slave-work on worlds like Bachian IV. Gor are the most common breed of beastman in the sector, and indeed the Imperium, they are an incredibly strong breed of human-beast hybrid with goat-like heads with muzzle-structures and often exaggerated canines as well as horn-like growths, these form the bulk of genetic stock imported and modified by House Vilas-Lobo to serve as their labour and slave forces. The tribes of modified Beastmen of this breed from the surface of Bachian IV live in matriarchal mining-clans lead by 'Clanmothers' although the majority of the slave-stock remain on the planet some receive sanction to leave the world when the Crusade is willing to pay the Vilas-Lobo's fee to free them for Crusade service, where they are funneled into the front-lines of battle.
The Vilas-Lobo stock are not the only beastmen in the sector however, on Caracas, the planet’s high mountain ranges and high plateaus possess a number of avian beastmen known locally as the ‘Ēkara’ (Homo sapiens accipitridae) who live in a tribal state mirroring that of the low-lander human tribes of the Taurekareka. Swift and fast with keen senses of vision, these beastmen are occasionally rounded up by Crusade expeditions and exported from the world to serve as helot scouts ahead of the bulk of Crusade forces, and are prized as helots by Nobles who take great pleasure in the sport offered by the fauna of the planet for which the Ēkara are valuable as spotters and guides.
Felinids (Homo sapiens hirsutus) are feline-like beastmen from the distant world of Carlos McConnel, possessing feline retinal structure means their visual acuity is highly diminished comparative to a baseline humans however their enhanced low-light vision compensates for this – between long talon-like claws they make expert ambush fighters in close quarters and serve as excellent long-range skirmishers. So far from their homeworld the only known examples of this species exist within the retinues of Rogue Traders as well as Auxilia regiments of the Prosperitas Crusade.
Dwellers (Homo sapiens marfaius) dwell within the deep marshes of the planet Carthusia, believed to be the remnants of some original human colony on the world long before the arrival of Imperial colonists in M.41. These semi-aquatic humanoids are distinguished by their eerily long limbs and digits (often webbed), flexible joints, large, darkened eyesockets and vestigial gills, and are locally called Dwellers a name to which they have accepted and adapted. The Dwellers have access (and indeed the ability) to use limited Imperial technology as well as using more sustainable technologies for their rural low-technology environment such as crossbows. Most of these communities have been converted to the Imperial faith, and enjoy a degree of accepted trade with Imperial settlements on the planet. The Imperium largely views the Dwellers as loyal, if repulsive examples of genetic deviance, and offers them service in the Imperial Guard where they are used as amphibious assault troops in support of Imperial Guard units using more expensive amphibious assault technologies. Few Dwellers travel outside their communities for any other reason then to serve the Guard as Auxiliaries
Because they cannot hide what they are, most Beastmen are kept clearly confined to reservations and work-camps where they have to work alongside humans - if they have to travel to however they travel with their appearance covered, a pure human to vouch for them, or in chains. The Imperium generally considers Beastmen to be 'useful' enough to preserve their use providing populations display no genetic instability, when that instability DOES occur the Imperium is often swift to act, without mercy, exterminating loyal populations of Beastmen just to prevent the possibility of chaotic mutations tainting the wider populace or being accepted within the Imperium as helots.
Mutants in the Prosperitas Sector
Humans and Abhumans determined to be beyond acceptable levels of genetic deviation from humanity, or that displace unstable genetics or spontaneous physical changes are all classed as mutants. Mutations can occur for a number of reasons many of them fully biological in nature, sometimes as a result to mutagenics in a local environment, sometimes as a result of experimentation upon humans by Imperial scientists or others - unfortunately for mutants like this, many mutants are the creation of exposure to the energies of the Warp and have a strong connection to the dark powers from that place. It is as a direct result of this that the Imperium condemns all mutants to sub-human classification and the very bottom of society, some mutant populations are tolerated, where the touch of the warp is not obvious, but these populations are an underclass of slave-workers more than anything else, always on the knife-edge because if the Imperium detects signs of warp taint within a mutant community, it will quickly move to exterminate it without mercy or thought.
Most mutants are abandoned at birth by their parents, no Imperial citizen wants the scrutiny that comes from having given birth to a mutant - these children are often left near mutant settlements and taken in by the community there, and raised amongst them. For these individuals a life of persecution by Imperial Citizens and Authorities awaits them, they are not entitled to any rights under Imperial law, they live upon the scraps and discarding of their genetic superiors. Often despite their persecution the Imperial cult flourishes amongst these desperate populations, often as an attempt to seek redemption for sins they did not ask for, often out of fear that should worship not be given to the God Emperor the Imperium will swiftly purge these wretches.
The mutant situation makes them vulnerable to the forces of the Archenemy and other foes of the Imperium who seek to exploit anger at the foul treatment they are given to worm their wretched ways into Mutant communities, corrupting them and turning them against the Imperium, often leading to uprisings against the Imperium from mutant populations. Fear of these uprisings drives Imperial paranoia, often leading to pogroms and mass slaughters of mutants as a form of population control to prevent mutant communities ever reaching a size where they could pose a threat to the Imperium.