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Warhammer 40K: Know Your Tyranid Hive Fleets

6 Minute Read
Mar 25 2024
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Admirals, prepare your vessels to engage the numberless Hive Fleets of the Tyranids!

Hive Fleets are massive locust-like Tyranid swarms, comprising billions of creatures including the actual bio-ships, living spacecraft used to cross interstellar space and the voids between galaxies. Each creature of the Hive Fleet is an inseparable part of the Hive Mind.

Hive Fleets Overview

An entire Hive Fleet is directed by the single coordinating will which is its Hive Mind, formed from untold billions of individual consciousnesses, each of which is a living creature in the fleet. Mankind still searches vainly for the higher beings they suppose control the Hive Fleets, and though such mighty creatures exist, they no more control the Hive Mind than single brain cells control a man’s body. It is the sum of the Hive Mind which motivates it, not its constituent parts.

Tyranid Hiveship battleship equivalent

Three major Hive Fleets have invaded the galaxy, each coming into conflict with the Imperium. Of the three major Hive Fleet invasions, two entered the galaxy through the Eastern Fringe, but one is moving up from below the galactic plane. The Hive Fleets encountered thus far are just a splinter of the main Tyranid invasion force that is traveling through the void between galaxies.

Void Prowler cruiser equivalent

The bio-ships contain everything required to sustain the fleet; some ships being purely for crushing resistance, the larger ships contain birthing pools to create the huge land armies of the Tyranids and even more ships when the need arises. The nutrients used as food and raw material are replenished by scouring conquered planets of every cell of biological matter, including all the Tyranids it seeded onto the planet. Because the Tyranid forces are recycled in this way, the “design” of the Tyranid warriors can be altered by genetic engineering, allowing the Tyranid forces to rapidly adapt to overcome any enemy. Further, the Tyranids absorb the DNA of defeated enemies, allowing for further genetic diversity. It is believed the Genestealer and Broodlord are derived from Human DNA, the Zoanthrope from Eldar and the Biovore from Ork DNA.

Strangler Kraken frigate equivalent


By the adaptive nature of the Hive Fleets, fierce resistance on a planet will only make the fleet stronger in the end; for this reason only a few tactics have been found to work. The first is to draw the Tyranids into a large ground battle, forcing the fleet to deploy as large a ground force as possible. Once this is achieved, the planet is evacuated, following with Exterminatus as the Tyranids strip the life of the planet. This tactic is effective as Hive Fleets are dependent on the impetus gained from absorbing each conquered planet; the Hive Fleet will also have lost the biological “energy” expended to conquer it, including all of the bio-material of the ground forces and by the nature of Exterminatus will not be able to recover any from the planet. This tactic is extreme and also damaging to the Imperium, as it destroys a valuable and habitable planet every time. It has been projected that there may not even be enough habitable planets in the galaxy to stop the Tyranid threat, especially if more Tyranid fleets arrive from outside the galaxy.

Major Tyranid Hive Fleets

Tyranid Ravenors of Hive Fleet Behemoth

Hive Fleet Behemoth was the first Tyranid Hive Fleet encountered by the Imperium, and was also the first contact the Imperium had with the Tyranids as a race. Behemoth made a juggernaut rush into the Galaxy from the Eastern Fringe and proceeded into Ultramar, resulting in what became known as the First Tyrannic War. It was eventually destroyed at the Battle for Macragge in 745.M41 or 746.M41 depending on the source.

800px-IyandenBattleBio-Titans of Hive Fleet Kraken fighting Eldar of Iyanden

Kraken was the second major Tyranid Hive Fleet to invade the galaxy. It was responsible for the Second Tyrannic War, occurring in 993.M41.


The invasion began 250 years after the last Tyrannic War and the destruction of the hive fleet Behemoth. An armed presence had been maintained in the galactic southeast, which members of Earth’s Administratum began to question the need for, arguing that Behemoth had been the sum total of the Tyranid race. When worlds along the eastern fringe began to erupt in rebellion, terrorism, riots and sabotage, the same adepts claimed the people were dissatisfied with living amid an armed camp. Among the first worlds known to be consumed by Kraken were Sotha, Miral, Graia and Radnar.

Hive Tyrant of Hive Fleet Leviathan

Hive Fleet Leviathan is the largest and greatest Tyranid Hive Fleet to invade the Galaxy. It attacked in 997.M41 from the galactic south. Unlike the majority of previous Hive Fleets that attacked from the Eastern Fringe, Leviathan instead skirted under the galactic rim of the galaxy and then pushed upwards through the galactic plane, spreading its forces across a broad front that covered the Ultima Segmentum, Segmentum Tempestus and even into the Segmentum Solar. Leviathan’s strategy was to form its forces into two giant tendrils hundreds of light years apart in such a way that it stretched the Shadow in the Warp over the vast distance between the two tendrils, stopping all psychic contact between the trapped worlds and the Imperium and also blocking Imperial reinforcements from navigating the Warp towards the beleaguered worlds.

One of Leviathan’s main tendrils, which was on a projected course directly to Terra, was eventually stopped at Tarsis Ultra. However, Leviathan as a whole remains undefeated and continues to assault the galaxy. Thus far Leviathan has consumed countless worlds. In response, the Imperium is reinforcing entire Systems, raising thousands of armies and dispatching dozens of Space Marine Chapters to troubled areas; meanwhile, several Eldar Craftworlds are using ancient destructive weaponry to reduce planets to Dead Worlds, and the T’au are developing new technologies and weaponry to combat the Tyranids. However, Leviathan is only being slowed down rather than fully destroyed, and it continues to assault all life in its path. It suffered a massive defeat at Baal by the Blood Angels chapter, and their Sucessor chapters.

Leviathan’s Return
At the end of the millennia, after their seeming defeat at Baal, the Imperium was beset by a newly evolved Hive fleet Leviathan, now the largest yet encountered with myriad new unseen Tyranid organisms. It has struck the galaxy from the quiet and relatively undefended Segmentum Pacifica, far to the galactic west. Reeling from multiple conflicts on too many fronts across the galaxy, the Imperium is exposed and militarily out of position. Already hundreds of worlds in the Segmentum have fallen to this invigorated Leviathan.


800px-HiveFleetsMapCurrent Hive Fleet Invasions

Learn the different types of Bio-Ships in the Hive Fleets


The Shadow in Warp grows…Will you succumb to the Great Devourer?

Author: Adam Harrison
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