"Warning, approaching vessel: this planet is quarantined and has been declared perditionem in aeternum by order of the Office of the Praefectrix, the Holy Askelline Synod, and the Ordos Askelline. You are entering a nominated exclusion zone and will be fired upon by vessels of Battlefleet Askellon if you continue on your current course. Turn about, say again, turn about...Warning, approaching vessel: this planet is quarantined... "
-Automated warning signal from Kul Exclusion Zone Orbital XVIII
Kul is an arid, empty desert world, haunted by sandstorms and dust devils that skitter across its crumbling surface. The planet is covered in rough sandstone; the deserted ruins of moderately sized frontier settlements and ghost towns dot its surface unevenly, their streets empty of all save the winds and the merciless light of Kul’s white-gold star. Kul idles at the end of a winding, fading cul-de-sac Warp route that branches away from a score of uninhabited systems. In the ordinary course of events, the world would have been left to its own devices, allowed to stagnate, been forgotten. However, in light of its tragic, eldritch, and horrific history, Kul has been soberly appraised as a clear and present danger to the moral and spiritual well-being of the entire sector.
As such, Kul has been quarantined and blockaded, locked away from the ordinary starfarers of the region by a number of orbiting defence platforms and the attentions of a small and increasingly strained Battlefleet Cyclopia taskforce. Now, the attentions of the sector’s most opportunistic recidivists turn to the dead world like moths to a flame by persistent rumours of Warp-flotsam of incalculable value. These greediest and most rapacious practitioners of the Faceless Trade thoughtlessly dice not only with their own souls but with the souls of countless others across Askellon, for the taint that settled upon and destroyed Kul may yet claim other worlds.
Kul’s early history is lost to antiquity. From its earliest recorded days, though, it had an unimpressive reputation as a frontier backwater with little strategic value; even after thousands of years of occupation, its inhabitants achieved little to advance their world. The populations’s failure to cultivate worthwhile exports did little to endear the system to any outside agency. Such records pertaining to Kul’s early history that do exist are universally scornful regarding the planet’s inhabitants; their appearance, morals, and intellect apparently having been something of a low jest in the Cyclopia Sub-Sector.
A factor in the planet’s unsavoury reputation may have been its relationship with the local Warp conditions. Always unpredictable, even by the terrifying standards of the Askellon Sector, the Warp tides around Kul were particularly prone to bizarre surges, rendering interstellar navigation to the system a tricky proposition at the best of times, forcing ships to exit the Immaterium far from the normal translation points. Ships that traversed these fluctuations found that these voyages invariably coincided with increases in shipboard mutant births and violent crimes, contributing to the planet’s dire standing. Over millennia, the isolated planet became perceived among Askellian powers, rightly or wrongly, as an unsightly stain undeserving of attention or support.
As if commenting sardonically upon this perception of Kul, nearly a millennia ago, after a period of relative inactivity lasting two centuries, the Pandaemonium suddenly snapped into life, turning and thrashing like a great ocean predator, throwing shipping across the entire region into disarray. The veils of reality around Kul shattered, and the entire planet was drawn into the Warp in a matter of seconds. This anomalous event caused tremendous consternation among Askellon’s rulers on Juno; while Kul and its people were of no moment in and of themselves, the fear of a similar event happening to a world that actually mattered concerned them gravely. However, in a sector where new threats arise all the time, this event was quickly forgotten, and not a thought was spared for the population of the world.
Roughly a hundred years later, a remote Adeptus Mechanicus monitoring station within the Cyclopia Sub-Sector reported that transit photometry of Kul’s star revealed the presence of an anomalous planet in orbit. Kul had returned.
A hastily-arranged scouting force from Battlefleet Cyclopia investigated and discovered that the prodigal planet had been irrevocably altered by its sojourn in the Warp. It appeared at first glance depleted of life, a world of vast dustbowl deserts and stagnant oceans. Most townships were in ruins, but some areas appeared frozen in time, with plates full of still-fresh food carefully set on tables and eating utensils embedded in dripping meats, meals interrupted forever. Old, clotted bloodstains mark other surfaces with signs of struggle and violence; evidences of gunfire, extensive weapon discharges, but no sign of what was responsible for the carnage. The world overall retained a hellish and unsettled psychic aura of atrocity, fear, and horror.
Disquietingly, no survivors could be located in the first sweeps, though anomalous distant fires, unsettling screams in the night, and uneven footprints dogged the footsteps of the Naval ground teams. Bafflingly there were bodies-thousands of them-but they were not of the native Kuln. Instead of the expected remains of Kul’s citizens, scouts found the horrifically twisted corpses of the Jakaan 11th, a regiment of the Astra Militarum lost in the Warp centuries previously. Their bodies, some as fresh as the day they died, others mere bleached bones, were alternately left fresh and unmarked, scarred beyond recognition, or melded together in the most nauseating fashion. To see such insanity was enough for the armsmen of the Navy, and they retired in haste to their vessels. Their missives alarmed the Sector Praefect, and grand-sounding orders were placed decreeing that the world be sealed eternally against intruders of all stripe, "lest the doom brought upon Kul be brought upon other worlds of our domains."
Originally a trio of cruisers led the blockade, but over the centuries there has been a serious degrading of the squadron’s capabilities. Now only a single Naval vessel guards the Warp-approaches to the system, the slow and underpowered Askellian Sica-class corvette Righteous Custodian, with twenty poorly-maintained servitor-operated defence platforms guarding the inner approaches to the world.
Kul is now quarantined, a ghost world of bone and dust. What few know is that there were indeed survivors, both in mortal and spirit form, that hide themselves amidst the remains of their old homes and the inhospitable reaches filled with the decayed, tortured bones of long dead soldiers. The living are few, but they still retain their hardy, frontier ways. Most were driven insane or mutated beyond belief in what seemed like only a moment’s exposure to the terrible energies of the Warp, but the communal spirit remains strong, and they refuse to abandon anyone. All know that certain death faces them should the Imperium discover their existence. Some still manage to make their way off-world-often by paying their way with the tainted items that were washed up upon Kul from its time within the Immaterium.
The peculiar circumstances of the world’s demise have acted as a siren call to those scavengers, heretics, and Warp-dabblers entranced by the leavings of the sickening entities that lurk beyond. Those with a working knowledge of the ways of the Sea of Souls recognise in Kul that rarest of Askellian Warp-phenomena, the Eye of a Warp Gyre.
The Warp is often likened to a planetary sea, and the comparison is apt if simplistic. The Warp has tides, currents, and predators. Also, like a normal sea, its great tides occasionally give up their treasures, washing up artefacts from within their unknowable depths upon the shores of reality. These "shores" are rare and transitory; where they appear on a permanent basis, they are known as the Eyes of a Warp Gyre. Kul, haunted as it is, is such a place, a tainted tidal pool of the Warp, and great treasures, in the form of ancient Warp-detritus, can be found washed up upon the banks of realspace.
Like an ocean floor littered with the wrecks of ancient maritime vessels, Kul is dotted with artefacts from every era of human Warpfaring history, both large and small: archaeotech, acidic lengths of glistening tentacles, dataslates of ancient texts in languages long forgotten, daemonic remnants foul and obscene, still-smouldering footprints burned into solid rock, gleaming starships sunken into gigantic deserts, and other forbidden treasures. All lie waiting for discovery on the surface of the planet, and for those who risk anything to retrieve them.