Genestealer Cult
A Genestealer Cult is a type of heretical cult in the Imperium. These are tucked away hidden places of the Imperium, with only the most humanlike of their followers seen during the leadup to an insurrection that sweeps away all that opposes them. The genestealers are a vanguard organism of the Tyranid hive fleets and use them to take over worlds of host species. Most worship the Tyranids thinking they are a Star God, and this is exploited to the full by the Tyranids who need a constant source of biomass to survive.
Structure
The cult is made up of layers made of generations, with specialists appearing in certain generations. The structure of it makes it appear as a multigenerational extended family. At the top is the nigh-immortal Genestealer Patriarch, a Xenos vanguard creature of the Tyranid species. They sneak aboard ships on infected planets, or sent out in spores by the hive fleets, attracted to planets rich in biomass. Whichever way it ends up on the planet it infects a sentient species with an ovipositor, allowing some genetic components to rewrite the DNA of the victim creature. At this point the genestealer grows in size, and it's psychic powers grow. Both it & any other genestealers infect as many of the local population it can, bring more locals into the fold.
When this happens, the host species births a monstrous child more in line with the genestealers than the hosts. The hosts are overly protective of any child they have, and they keep them from view of any uninfected. Both continue breeding, and a second generation is born with slightly more aspects of the hosts. Both of these generations live in regions around & close to the Patriarch, acting like bodyguards, advisors, and shock troops.
The third generation is then born with more of the host species showing physically, usually with vestigial features of the genestealer heritage, compared to the previous generations. These are enough to be able to pass in the general population if not viewed to closely. The fourth generation in then born from them, and can easily pass for the host species, and usually their genestealer heritage is small enough to pass as naturally occurring mutations or by environmental factors. Eventually a number of purestrain genestealers are born. This can continue for generations.
Each of these generations, and any hosts are linked by a strong psychic bonds with the patriarch at this spider web of synaptic network. Each generation is looked upon as being closer to the patriarch than the lower generations. Eventually, a large enough cult will spawn three specific organisms, a Magus, a Primus, and a Jackal Alphus. The latter is a specific adaptation whose purpose as to lead fast moving bikers & outriders of the cult, and acts as psychic beacon for these. The Primus is a war leader, born with the skills needed to lead the cult in uprisings, and usually appears when the cult has grown large enough to take over a planet or in response to stress factors such as invasion of the planet (especially by the likes of Orks or Chaos). The Magus is unique, as they are normally born at least once every 4th generation, if not more due to size. They are born from the most psychic individuals of the host species the genestealers can find. They act as the cult's mouthpiece, and as a conduit for their hive mind.
Culture
The the Patriarch, 1st & 2nd generation cultists hide away working in the background for when the cult grows large enough to take over the planet they inhabit. The 3rd & 4th generations work diligently at whatever tasks they are assigned by the Imperial overseers appearing as model citizens. They use this time to gather intelligence, equipment and other odds & sods that would benefit the cult, and carry out espionage too if at all possible.
All this is to protect the cult from discovery and to protect the core members, all for the time of the uprising, and the belief that when they do, the Star God or Gods arrive to welcome them with open arms. Sometimes they preach too, about how the 'Star God' will lift up the people and make them whole with the universe. This will usually appear as a corruption of the Imperial Creed, and the Emperor will appears in a blasphemous form, if viewed by outsiders.
Public Agenda
They look to subvert the host world to their own cause, believing that only they can save it from a harsh uncaring universe.
Assets
The cult will end up with many specialists, such as the Magus, Jackal Alphus, and Primus. They will have elements like the Nexus (a specialist in war co-ordination) and such like to bolster their ranks.
Tunnels, stockpiles of equipment, vehicles, weapons & explosives will be secreted away in hidden locations, or freshly made. Since they have many elements of their host species they have access to anything that the latter have in some capacity.
History
The Imperium is unaware of how long Genestealer Cults have existed in the galaxy. The first contact with such creatures was the genestealers of the Ymgarl moon, and were thought to be indigenous to it. After the Tyranid hive fleet Behemoth first crashed into the Imperial borders, it was found that they had genestealers as part of the force so immediately sent the Imperial Fists space marines to eradicate the Ymgarl genestealers.
After that nothing was heard of them until an incident on the planet of Ghosar Quinus where Inquisitor Chaegryn had disappeared. At the time, renowned Chaplin Ortan Cassius of the ultramarines Space Marine Chapter had been serving in the Deathwatch. When his team descended into the bowels of the mining colony they soon discovered the true extent (and reasoning) behind a genestealer cult. After fighting their way out and reporting back to the Deathwatch, the Imperium found out the threat that these posed.
As for the cults, each one is started at different times when a genestealer finds it's way onto a world that is inhabited by a spacefaring species that it infects. The first genestealer to do this goes through the process of turning into a Patriarch, and any other purestrain genestealers become valued elders. From the beginning the cult grows. Exactly how, when, or even if, a genestealer cult forms is unknown in many ways. The only known variable is when a genestealer arrives on a planet is there a risk of it starting.
Disbandment
Only two ways will truly stop a cult, ands wipe them out.
The first is a military conflict that destroys enough of the cult to stop it functioning.
The second is the most terrifying. What the purpose of the cult is known only to a few. It is nothing more to undermine societies of spacefaring species, and to act as a beacon in the Warp. The beacon itself is generated by the genestealers, their broodkin, and related organisms, and linked by the Tyranid genes these creatures now carry. This is picked up by the hivemind of a Tyranid fleet nearby, and the strongest of the genestealer beacons will attract a greater amount of Tyranid bioships of a fleet. From there the Day of Reckoning begins when the Tyranids make planetfall and proceed to eat all biomass including the host species. Only then do the latter realise what is happening, and the genestealers are subsumed by the hivemind, and sent out once again to infect another world.
Mythology & Lore
All Genestealer Cults believe in an End Times, and when they are strong enough, they are to rise up and await the Star God to land, and save them.
This can be in any number of specifics, and no major cult has the exact same details as to what the Star God will look like, or even what it is. Just believing in it is the important thing and the Patriarch is the messenger / child of such a god. Little do they know the truth though.
Divine Origins
The origins of such belief is ingrained at a genetic & psychic level felt throughout the whole cult. This has been encoded into the genestealer DNA to allow for any offspring to follow the genestealer without question, and allows for the genestealers to dominate a given host species.
Priesthood
The Magus, Iconward, and the Patriarch fulfils a triptych of saintly figures that are worshipped by the rest or at least recognised as their mouthpieces.
DISBANDED/DISSOLVED
"The genestealer is a curse
Type
Exotic, Gestalt Consciousness
Predecessor Organization
Leader
Parent Organization
Related Species
Comments