"Imperious Fortis actual to T'au flagship: Cease fire. I say again, cease fire… we… we surrender."
- —Captain Tylian Kynassis, 145th Scintillan Battlegroup.
The planet's wealth of natural resources means that both sides regard it as extremely valuable, yet that same worth has resulted in a world which is inimical to Human or T'au life.
However, it is not merely mineral resources that draw the gaze of Human and T'au alike to Pelegius, and it is not merely the toxin-saturated, irradiated environment that poses a threat to those who seek to claim this bounteous world.
Whatever occurred in Pelegius' past, it has left remnants behind to be discovered by the curious and the avaricious.
Lurking beneath the desert sands are monstrous invertebrates, mutated by countless generations of rad-exposure and grown to colossal proportions with no greater predators to challenge them.
Clutches of dormant macroscorpion eggs and nests of hibernating tyrannopedes are amongst the perils awaiting those who find themselves on Pelegius, awakening at the slightest disturbance of their otherwise-barren habitat.
Deep beneath the surface, remnants of a different sort can be found by those willing to search for them. Ancient ruins of a long-dead civilisation exist kilometres beneath the shifting sands, and both Human and T'au excavations into these ruins have only provoked greater curiosity.
The T'au wonder at the technological marvels that could have built these glittering cities and at the cataclysm that saw them abandoned and buried, while the Adeptus Mechanicus vocalise binaric litanies of warding and sanctity as they delve into ruins that are as likely to be a fragment of Mankind's Dark Age of Technology as a broken shard of an alien civilisation, in search of the long-lost secrets that they know must reside deeper within.
Upon the surface, a bitter conflict rages between armies of fast-moving skirmishers and heavy vehicles, with both sides relying on the protection of advanced rad-warded armour, rebreather systems and the sturdy hulls of battle tanks to stave off the hostile environment as they engage in a long and vicious series of raids and feints.
Tens of thousands of Skitarii troopers, their augmetic forms largely immune to the poisons and radiation that would slay normal troops, supported by elite Astra Militarum forces clad in hostile environment suits, clash against environment-hardened T'au Battlesuit teams of ever more sophisticated design.
Pelegius is an exceptionally valuable resource world, and consequently subject to considerable attention from the Adeptus Terra. Further, military action by the T'au has required a large garrison force to be deployed.
The world has considerable worth as a mining colony, with new sources of rare or valuable materials discovered regularly by the extensive survey expedition. The hostile conditions are regarded as an obstacle worth overcoming to benefit from a world so rich in minerals vital to the ongoing Imperial war effort in the Jericho Reach.
The presence of the T'au demonstrates that they crave such valuable resources as well. Continual supplies of food, potable water, and medicae consumables (primarily counterseptics, antitoxin and anti-radiation drugs) are an absolute necessity.
Geography and Climate
Pelegius is a world inimical to Human life, toxic and radioactive to a point that an unprotected Human will sicken and die within solar days.
These conditions are not only lethal to Humans; there is little organic that can withstand such horrific conditions, and all but the hardiest of creatures will struggle to exist on Pelegius for long without sophisticated protective equipment or equally potent natural advantages.
The macrofauna native to Pelegius is immune to the effects of their world's environment, having evolved to withstand it over countless generations.
Yet the planet is also possessed of extensive, naturally occurring mineral resources, the overwhelming majority of which are valuable to the ceaseless industry necessary to keep the Imperium functioning. This abundance of natural wealth makes Pelegius extremely important to the ongoing Achilus Crusade.
With sufficient labour and after the development of an appropriate infrastructure, Pelegius will be able to support potentially as much as a tenth of the projected raw material requirements of the crusade, and the expeditionary government on the surface have advised that the planet be assigned a Tithe Grade of Exactis Extremis.
Pelegius' abundance of resources is believed to be a major contributor towards its inhospitable nature. Many of the raw materials discovered on Pelegius are extremely toxic, radioactive or both, and combined with the world's comparatively close proximity to its powerful white star, has resulted in a level of ambient surface radiation that builds to lethal levels in a Human body after mere solar hours of exposure.
Little is known about the early history of Pelegius. Few accounts of it remain from the time of the lost Jericho Sector, and it seems that there may have been little to begin with, the world having been a blasted wasteland since long before the Great Crusade.
If any during that time discovered the mineral wealth of Pelegius, or the ancient ruins beneath its surface, no evidence remains of their discoveries.
Regardless, whether the world was known to the Imperial authorities within the Jericho Sector or not, it was identified by forward scouts for the Achilus Crusade while the Iron Collar was being initially fortified, and marked as a world requiring investigation rather than military intervention. Six solar months later, an Imperial Navy battlegroup led by Captain Tylian Kynassis moved into the system to conduct a preliminary survey, only to discover that the T'au had arrived there first.
Faced with a newly deployed waystation and a significant T'au force surveying Pelegius itself, the Scintillan 145th Battlegroup was heavily outgunned and caught by surprise in a battle that left most of the group as drifting hulks, and ended with the battlegroup's captain and the flagship Imperious Fortis surrendering to the T'au.
When word of this reached the crusade's High Command, retaliatory actions began almost immediately, directed not only at the T'au, but at the traitorous Captain Kynassis.
The magnitude of this reprisal was, however, limited by the needs of Operation Hammerfall, and while the T'au fleet was driven from Pelegius' orbit, it was not without cost to the Imperial Navy. With the world now freed from xenos dominance, the personnel of the Adeptus Mechanicus began to move in, the survey ship Meticulous Scrutiny arriving two solar days after the retaliation force had given the "all-clear."
After a survey lasting for eight solar weeks that saw hundreds of Servitors, menials and lay-technicians succumb to the hostile environment and indigenous macrofauna, Magos Thaniel Axiom declared the world to be rich in valuable natural resources and sent a series of astropathic messages urging that Lord Militant Tiber Achilus begin the exploitation of those resources as soon as possible.
However, in spite of their trickery, the T'au could not completely drive the Imperial fleet from the system, and both sides withdrew to the clustered asteroid fields and gas clouds at system's edge to regroup and prepare for a renewed assault. In the solar decades that have followed, this state of affairs has changed little.
Neither force can easily gain the upper hand against their enemy due to a slow trickle of reinforcements, sufficient to replenish losses but insufficient to give a significant advantage, due to the more desperate needs of other war zones.
A long war of intermittent skirmishes have characterised the void around Pelegius for a very long time. Amidst this, a similar ground war has sprung up, with both T'au and Imperial forces clashing across vast expanses of irradiated desert while engineers, archaeologists and administrators seek to uncover the secrets of Pelegius.
The oldest and largest of the Imperial settlements on Pelegius, Outpost Aleph is a colossal latticework of shielded, self-contained hab-domes connected by environment-sealed tunnels that span an area more than eight kilometres across.
Equipped with powerful vox and augury systems to pierce the interference caused by Pelegius' high background radiation, Aleph serves as the central command centre for all Imperial scientific and military operations across the planet, and its outermost domes are heavily fortified to serve as bunkers and barracks for the Astra Militarum and Skitarii garrisons.
What few know about, however, is the true extent of Outpost Aleph. At the heart of the complex, unseen by all but the Tech-priests who work there, is the Aleph dig site, the true reason for the complex's location.
Extending more than sixteen kilometres below the surface, the dig site took the efforts of thousands of Servitors, menials and lay-technicians to excavate, and dozens of Archaeosavants and other Tech-priests to study and catalogue the artefacts and ruins found within.
Their findings have been woefully inconclusive as of yet. While the inhabitants are likely to have been humanoid, almost nothing remains that suggests whether the ruins are of Human origin or xenos construction.
Worse, a string of serious industrial accidents have claimed the lives of hundreds of menials and destroyed thousands of Servitors over the past year, while several Tech-priests have simply gone missing during forays into the deeper zones.
Thanks to the presence of infiltrators in service to the Inquisition, investigation of these incidents is underway, with many suspecting that whoever created the ruins may not be entirely gone.
A ring-shaped mountain range enclosing a dune sea some eleven hundred kilometres across, the Tirmorodan region has been the site of more clashes between Imperial and T'au forces than almost any other region on the planet, with neither side able to gain a foothold in the dune sea for more than a matter of solar weeks.
The Tirmorodan Mountains themselves have been identified as a particularly abundant source of metals valuable for the production of starship armour, while the territory within the ring is believed to be home to one of the largest archaeological sites on Pelegius, though neither side has been able to accurately confirm this due to the almost ceaseless hostilities.
The passes leading through the mountain range are heavily guarded and key positions have been extensively fortified, serving as strong-points from which both T'au and Imperial forces can launch raids and expeditions into the dune sea.
As each side pushes deeper into the contested territory, temporary encampments are established to allow scientists and engineers an opportunity to delve beneath the shifting surface and learn of what exists under the sands.
Ambushes and raids swiftly condemn these opportunistic digs to failure, leaving the bodies and equipment to be buried beneath the ever-changing dunes. These attacks are met with swift retaliation, with the Imperium and the T'au denying one another the opportunity to study the region in more detail.
Yet some doubt exists. While those of a military inclination are swift to blame their foes for each failure, a small but mounting collection of evidence suggests that a proportion of those lost encampments are just that -- lost, having been suddenly and inexplicably depopulated and destroyed by something other than Imperial or T'au weaponry.
Confronted with this evidence, most are quick to blame the deadly and voracious indigenous creatures or some attempt at deception from their foes ... for the prospect of another force on Pelegius that opposes both Human and T'au alike is a disquieting one.
Believed to be the location of the primary T'au compound, the Azkharraeon Flats are stable, rocky wastelands in contrast to the shifting sands that cover most of Pelegius, and they are found few hundred kilometres north of the equator.
Imperial expeditions have thus far avoided the equatorial regions of Pelegius, mainly due to the extremely high temperatures common there, but T'au physiology is believed to be far more capable of enduring high temperature/low humidity environments, explaining a greater willingness to establish themselves in places where Humans cannot thrive.
Scouting missions, performed by specially augmented Skitarii, have determined that much of the T'au compound is maintained and operated by drones, directed by a few hundred T'au engineers and scientists.
Limited pict evidence of the heart of the compound shows a device that appears to be an extremely potent fusion cutter, believed to be employed to drill into the dense rock of the Azkharraeon Flats, though what the T'au have found beneath the surface there remains unknown.
The T'au garrison on Pelegius appears to consist almost entirely of battlesuit-equipped infantry, as conventional T'au combat armour cannot provide adequate protection against the hostile environment.
Lighter battlesuits are favoured, and armoured environment suits of a similar design (though unarmed) are used by the Earth Caste personnel on Pelegius as well.
- Deathwatch: The Jericho Reach (RPG), pp. 66-69