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Warhammer 40K Lore: Tyranids And Synapse And You

4 Minute Read
Dec 8 2019

Gather ’round loremasters, today we’re discussing the various ways the hive-mind of the all devouring Tyranid swarms keeps them acting in deadly unison.

We have been cleared to bring you some information from the Biologos archives, courtesy of Magos Cimex, who has offered special dispensation to discuss the encroaching Tyranid threat, as they attempt to spill once more the blood of Baal. Ordinarily, the tyranids are little more than common insects–albeit with armoured carapaces, talons sharp enough to pierce even the thickest armor, and biological processes that convert biomatter to deadly plasma, and the ability to transform your genetic sequence converting you to one of their brood.

Deadly, to be sure, but like many insects, few are capable of operating independently. Their intelligence is less than animalistic–it is instinctual at best. They require the complex organisms of the Tyranid Hive Fleet to help spread the psychic field known as Synapse, which represents the collective malevolent intelligence of the Tyranids.

Synapse is the Tyranid Psychic Power which unites all of the Tyranids into the Hive Mind. It is projected by Synapse Creatures which are usually leaders such as Hive Tyrants, Tyranid Warriors and Broodlord or specialist psykers like Zoanthropes. These creatures have greatly increased synapse networks within their cortex and these act as psychic conduits for the Hive Mind to order nearby troops. Without the Synapse guiding them, most Tyranids will revert to a feral state, although some, such as Genestealers with their Brood Telepathy, can perform just as well without Synapse as they do with it.

This strong psychic field spreads across our galaxy, casting a great shadow across the warp. It is theorized that this Shadow in the Warp comprises the psychic consciousnesses of thousands upon millions upon billions of tyranid creatures, and is so powerful that it radiates out of Tyranids like a flood. This permeating psychic power on the gigantic scale of a Hive Fleet distorts the Warp for light years around the fleet’s position, preventing Imperial Astropaths from sending or receiving telepathic messages, stopping spacecraft entering the warp and forcing spacecraft already in the warp wildly off-course as warp travel becomes increasingly unpredictable. This invasive “shadow in the warp” sows terror and confusion on prey worlds as it traps and prevents the doomed inhabitants from calling for assistance. It even penetrates into the minds of nearby creatures and manifests as a primal malaise that can never be expelled. If a creature has psychic potential, the horror they feel is magnified tenfold and using their psychic abilities could drive them into incurable insanity. As a Hive Fleet approaches a target planet, whole populations will plunge into madness and despair even before the first Tyranids have made planetfall.

However, even this great gestalt mind cannot be omnipresent. They must direct the thousandfold arms of the hive fleets on campaigns across hundreds of worlds simultaneously. Thus it falls to the great and terrible Synapse creatures. These advanced bioforms are capable of independent action, and, perhaps owing to their comparatively large size enjoy a degree of battlefield autonomy. These Synapse creatures, such as the Hive Tyrant or the Tyranid Warrior, are able to telepathically exert the Hive Mind’s influence in order to control smaller Tyranid creatures, which without the Hive Mind would revert to genetically instinctive behavior of feeding and self-preservation. These Synapse Creatures focus the Hive Mind into nodal points that quell the natural instincts of nearby small Tyranid creatures and are essential for the swarm to operate effectively.


Even the Genestealers, those insidious old devils, have a form of this power. Their collective telepathic abilities manifest in the form of the Brood Mind. This is a smaller and more localised version of the Hive Mind is created by the interlinking telepathy of a Genestealer Brood. This Brood Mind is used to control host victims impregnated with Genestealer genetic material. It also fulfills the Genestealer’s role as infiltrators as the Brood Mind acts as a psychic beacon to draw a Hive Fleet towards the planet it is centered on. Then when the Hive Fleet comes within a few hundred light years of the infected world, a subliminal reaction is triggered in the Brood Mind to goad the Genestealers into a frenzy of killing and breeding. Thus collapsing the society in which they were hiding and making way for the Tyranid invasion.

It has been theorized that the Brood Mind functions to humans as Synapse does to tyranid creatures. Bear that in mind, and keep your own willpower strong–if you suspect your genetic material has been corrupted by Genestealer material, you are at risk of possession by an alien hive mind, and should take appropriate precautions with the nearest office of the Commissariat.

Take care, Loremasters!

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