Corruption of Karkan
The Hive Fleet was first encountered on the Hive World of Karkan in Segmentum Ultima. As part of the Great Hive Fleet Behemoth, this splinter was sent to skirt around the epicenter of the battle to surround and cut off reinforcements, as well as distract the enemies.
Karkan was taken quickly and brutally due to the activation of a sizable Genestealer Cult. Within a month the former Imperial World was being harvested of all life. The splinter fleet continued on its path of corruption and laid waste to a dozen worlds before the main Hive Fleet Behemoth was decimated through combined efforts of Space Marines and the Imperial Navy.
Throughout centuries there were reports of corrupted, monster ridden derelict ships and space-hulks floating through space. Lone sightings of creatures embedded into asteroids and the terrain of Dead Worlds.
Only recently the connection has been made between these lone events and a trajectory of these sightings spanning nearly the entire length of Segmentum Ultima has been drawn.
It is unknown at what point and under what circumstances, but Karkinos made its way to Aetna system outside Argus Sector and planted the seeds for a Genestealer Cult. It is believed to have been in the making for at least fifty years due to the speed and co-ordination with which Hive World of Aetna I was taken over. With a solid base of operations and plenty of bio-material, the rest of the world within the system fell quickly.
Sizeable enough to begin a corruption of an entire Imperial Sector, Karkinos made its way towards the Argus Sector , still ever elusive, planting and cultivating Genestealer cults on as many worlds as it can. To this day Karkinos is one of the major xenos threats within the sector and beyond.
Karkinos Fleet Tyranids have evolved through necessity to be as elusive and deceptive as possible. For hundreds of years the fleet was not even a fleet in its own right. Scattered throughout the void small pockets of Karkinos preyed on trade ships and nested in solitary Dead Worlds, always moving always untraceable. Imperial Trade fleets would not reach their destination falling prey to the tyranid ambushes to be later consumed. What could be extrapolated is that there was always a presence, a nexus point to where the scattered Karkinos pockets would always return to, undoubtedly on the move at all times itself.
This tactic adapted by the tyranids to survive after the defeat of Hive Fleet Behemoth translated into their regular combat strategy. This splinter fleet employs stealth and deception and rarely swarms over their prey like their parent fleet did, instead spreading out and biding their time until their enemies are weak and oblivious, before striking and harvesting them.
As such they also know when to retreat when their goals are not worth the losses.
Seeds of Corruption
While the fleet is in hiding, slithering through space it strategically plants Genestealers on potential prey-planets in hopes of cultivating a cult, preparing the world for an invasion.
It is unknown how many Imperial Worlds have been infected by the Karkinos fleet, but judging by the dormancy and low activity of the fleet the possibilities for damage are unimaginably horrific.
Once the Karkinos tyranids assess the size of the Cult and their own forces they strike. The mycetic spores from their bio-ships blot out the sky in a single massive assault on the unfortunate world, while the Genestealer Cult is activated and weakens the defenses as much as possible, softening the prey.
Once the assault is over and any resistance removed, bacterial agents and feeding organisms ravage the surface of the world for any bio-material before being collected into the Reclamation-pools through the capillary towers of the massive bio-ships.
The hive is supposedly being lead by one or more Norn-Queens who interpret will of the Hive Mind from within the two known Hive Ships. Currently there is only one known Hive Ship within the Argus Sector, after the second one has been lured into the Webway by Valara Vendel and her followers.
Due to the tyranid defeat on the now harvested Forge-World of Aetna and Hive-World of Meliae, by the combined forces of Blood Wights and the local PDF, Hive Fleet Karkinos has been scattered throughout the Argus Sector. Desperately trying to survive and consume it's only saving grace is the general lack of stability across the sector and no united effort to uproot the tyranid corruption.
The vicious Carnagore is an evolution on the already terrifying Ravener. Like it's predecessor it has six limbs four of which are scythe claws, while the last two are reserved regular claws, capable of carrying weaponry. Similarly to Raveners, Carnagore can travel underground and launch ambushes as it burrows from under the soil.
What sets it apart from it's cousin bioform is it's size and unique maw. Carnagores can usually reach the size of an Imperial Sentinel and are also prone to travel and ambush their enemies alone rather than in groups like its smaller cousin. A Carnagores maw is also much larger in proportion to its size. This is due to the biomorph of Toxin and Acid glands within its mouth and gullet. Another terrifying biomorph is the massive tongue of the tyranid. Another creature in it's own right it shoots out as the Carnagore opens its mouth, spewing acid or toxins and ripping its enemies to shreds with its death coated teeth or pulling them towards the Carnagores scythes.
This also makes Carnagore especially powerful at ambushing enemy heavy armor. As it burrows from under a Rhino or a Tank, it spews acid over its armor softening it up as the Carnagores tongue bores through it inside the vehicle ripping the crew to shreds or filling the vehicle with deadly toxins or burning acid.
Ladon is the infamous Harridan Bio-Titan of the Hive Fleet Karkinos. Perhaps the deadliest lone tyranid within the fleet, Ladon has been a scourge of many battlefields. It's piercing shriek was often the last thing people heard as it blotted out the sky with its wings and unleashed its Gargoyle brood upon the unwary, soon to be bio-soup.
Even during the battles where Karkinos was defeated and the great monster felled it shed its wings and burrowed into the ground, only to be seen on the next battlefield returning an even more deadly foe.
It has been noted by the survivors and victors who were unfortunate enough to battle Ladon, that it exhibits a sort of sentience akin to a Norn-Queen. It has been seen to retreat while the rest of the tyranid swarm marched into certain doom, and it has been seen to call out to other tyranids to form around it and launch an independent assault. It has been argued that perhaps this Bio-Titan is one of the 'interpreters' of the Hive-Mind much like the Norn-Queens, and thus this monstrosity is a high priority target for the Imperial Forces.
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