"Cadres 211, 261 and 272; hostile incursion in sector 74; an immediate response has been mandated by Shas'O Tsua'Malor Aloh'shas Elan'nan and ratified by Aun'ui Tau'n Len'ra. Form up as a contingent under Shas'el Tash'var D'ka Cha'ro. Air support is being allocated to you now, Shas'el. Tau'va!"
- —Fire Caste Strategic Command, D'Shas'Ka
D'Shas'Ka 4, which means "Twin Suns" in the T'au Lexicon, is the name of both a world and its binary star system comprising six planets found within the Canis Salient of the Jericho Reach. Controlled by the T'au Empire, it is currently under assault by the forces of Chaos.
The fourth world in the system, designated "D'Shas'Ka 4" or Seraph 131 in Imperial records, is officially regarded as a Xenos World, the system having been claimed by the T'au at some point before the launch of the Achilus Crusade.
Inquisitorial intelligence-gathering has determined that the world's government is called D'Shas'ka Shan'al, or the "Twin Suns Coalition", which is led by the highest-ranking T'au of the Fire, Water, Air and Earth Castes, presided over and advised on the true course of the Greater Good by a senior Ethereal.
For the Imperium, the specific identities of these individuals are unknown, but it is believed that they are not actually on Seraph 131 at all, but rather upon an orbital station above it.
The fortifications are somewhat uncharacteristic of T'au settlement, as the T'au are known to dislike defensive warfare, and are believed to exist primarily to fend off the intrusion of aggressive native flora and fauna.
The D'Shas'Ka System consists of six worlds, one of which is presently habitable, orbiting a mid-sized yellow star akin to Terra's sun, while a small white dwarf companion star orbits the edge of the system from a considerable distance, making translation into the system from the Warp dangerous to the unwary due to shifting gravity wells.
The habitable world, orbiting fourth from the primary star, has an irregular day-night cycle due to almost constantly bombardment with either direct or reflected light from one or both stars, with eclipses providing the few occasions of true darkness.
This abundance of light and warmth, and the world's ideal distance from both stars, has resulted in a fecund and verdant world regarded by the T'au as being ideal for habitation, though somewhat cooler and wetter than their physiology may be used to.
Located spinward of the Greyhell Front, D'Shas'Ka 4 is several solar weeks travel from any other world in the Velk'Han Sept, and represents the furthest extent of T'au-dominated territory from the Black Reef and Tsua'Malor.
However, in spite of such claims, D'Shas'Ka 4 is not a world entirely under the peaceful rule of the Greater Good. While largely unperturbed by the Imperium, D'Shas'Ka 4 is a world pressured by invasion from another front -- the Chaos-tainted legions of the militaristic Stigmartus Chaos Cult.
While clashes between the T'au and Stigmartus forces are not unheard of, they are rare, with the Stigmartus typically content to turn their fury upon other Humans, particularly the Imperium.
The Stigmartus do not regard the T'au as particularly significant when compared to their loathing for the Imperium, and tend only to attack T'au worlds when provoked or when some ulterior motive drives their cruelty.
The binary system of D'Shas'Ka, referred to by Imperial astrographers as Seraph 131, seems to be of some significance to a faction within the Stigmartus, driving their urge to stain its worlds and stars with the blood of the T'au.
The eventual goal of the Stigmartus on D'Shas'Ka's primary world remains unknown, in spite of careful scrutiny by the Inquisition.
A significant Kroot presence has been established on D'Shas'Ka 4, primarily because of the sheer density and aggression of the indigenous creatures. These Kroot have thrived on the verdant world, and continue to do so, with a fourth generation of D'Shas'Ka Kroot beginning to appear in the last solar year.
The T'au colonists, however, have not been as successful. Earth Caste xenobiologists struggle to catalogue the sheer quantity of species to be found on D'Shas'Ka 4, and rigorously drilled cadres of Fire Warriors are on constant alert to repel attacks from particularly tenacious wildlife or from Stigmartus forces making planetfall, seldom staying in one place for more than a few solar weeks at a time.
Particularly troubling to the leaders of the D'Shas'Ka Coalition is that the diversity and viciousness of both the local flora and fauna and the frequency of Stigmartus attacks has been increasing steadily for the last Terran decade, and while the Shapers of the Kroot gladly embrace the fury of the wild as a challenge to be overcome, the T'au are less pleased with this development. Their anxiety has only increased with the first forays of the Imperium to D'Shas'Ka.
In place of a warfleet aimed at xenocide and conquest, swift and stealthy courier vessels have represented the overwhelming majority of the Imperial intrusion into the system, with each and every one of them bearing servants of the Inquisition.
Each visitation has heralded a series of high-level negotiations, with the adepts of the Inquisition conferring with T'au diplomats for weeks at a time before departing silently.
Unknown to the T'au, these missions are the operations of a coven of Ordo Malleus Inquisitors who have been observing and working to counter the actions of the Stigmartus, following a string of omens and prophecies that revolve around the heretical organisation.
Seeing a pattern in the Stigmartus attacks on D'Shas'Ka 4, members of this coven have acted to bolster the T'au defence against Chaos-aligned forces and guide their hand to combat such foes without overtly showing their involvement.
Following usual T'au tactics, there are few static defences throughout the system; instead, the T'au rely upon scattered drone-controlled sentry stations and a fast-responding defence fleet operating from the orbital station above the fourth planet (which also serves as the primary Air Caste habitat for the T'au colony in the system, the Air Caste being physiologically unsuited for life on a planetary surface).
The colonial efforts on D'Shas'Ka 4 are somewhat different from conventional T'au strategy, however. So vital and aggressive is the indigenous life that the T'au have been forced to establish fortified compounds to maintain an effective presence on the surface, using these scattered strong-points as the primary settlements from which to engage in forays into the dense forests.
The Argent Revelations
Prognosticator Gallius, a Silver Skulls Librarian serving within the Deathwatch centuries ago, penned a massive tome of prophetic visions witnessed over his decades of service, which to this day resides within the Librarium of Watch Fortress Erioch, studied by Librarians and Inquisitors alike.
Over the centuries, it has given a remarkable amount of insight into threats faced by the Deathwatch in the Jericho Reach, to those with the wit and will to decipher the cryptic words and sigils.
One of these transcribed visions speaks of "An angel under twin suns, and the branded legions who strive to defile her," which seems to refer to Seraph 131 and the Stigmartus forces assailing it, in a remarkably clear and lucid fragment of prophecy amidst thousands of pages that have taken countless savants to decipher.
The command centre for all Fire Caste operations within the D'Shas'Ka System, the Shas'ar'tol D'Shas'Ka is a sprawling complex of scanning arrays, vox-relays and buildings filled with drone-assisted substrate stacks, collating immense amounts of strategic and tactical information from every Fire Warrior Team, battlesuit and vehicle on the planet in order to provide accurate minute-by-minute insight into the state of every skirmish and firefight currently ongoing.
The T'au use of these technologies is commonplace in many warzones, allowing them to respond efficiently and coherently to enemy actions and take best advantage of the experience of veteran commanders.
The Shas'ar'tol D'Shas'Ka is staffed by several hundred Earth Caste technicians, Water Caste adjutants, and a select staff of experienced Fire Caste officers (typically those who have suffered debilitating injuries in the field and who cannot currently serve on the front lines), led by Shas'O Tsua'Malor Aloh'shas Elan'nan, a young and promising T'au Commander born upon the Velk'Han Sept's capital world.
Insertion Point Alpha
Unbeknownst to the T'au, the Inquisitorial missions to Seraph 131 have not purely served a diplomatic purpose.
Viewing a T'au world under attack by a mutual foe as an unrivalled opportunity to reach orbit undetected, an operation was undertaken during an early diplomatic mission to insert a mixed detachment of Inquisitorial agents, ranging from seconded Death World veterans, to infiltration specialists, xenolinguists, Tech-priests and a trio of astropaths, to observe T'au movements and report back to their masters.
Under strict orders to not engage the enemy, the observation detachment has established a central base of operations within a region largely unexplored by the T'au, while discrete teams move about the planetary forests and jungles for solar weeks at a time, working to intercept and decipher T'au vox transmissions, and awaiting covert supply drops from subsequent Inquisitorial missions.
To date, no extraction plan has been formulated that will not result in the cessation of diplomatic operations with the T'au, but the placement of the insertion group has resulted in Inquisitorial savants devising a number of distinct hypothetical infiltration scenarios, should conflict be required.
Many of these scenarios have been discussed at length with the Chamber of Vigilance of Watch Fortress Erioch, as one or more Deathwatch Kill-teams would be ideal for precision operations -- such as sabotage or assassination missions -- deep into enemy territory, or for spearheading a potential invasion.
None outside of the Inquisition and the Deathwatch so far know about Insertion Point Alpha, and only a few within those organisations are aware of its existence. For the time being, an Imperial invasion of Seraph 131 is purely hypothetical, as are any further armed missions into the system.
Literally translated as "the blooded earth," this region has been identified as a common place of conflict between T'au and Stigmartus forces, and much blood has been spilt there as a result. The frequent fighting is not why the place grows in infamy amongst the T'au, however.
Fire Caste forces who have fought in the area are known to have a particular dread and loathing for the region, for a variety of unsettling reasons.
The most worrying of these is an increased tendency for the T'au to be aggressive and short-tempered, even with bonded teammates, which has forced more than one cadre to be redeployed elsewhere on the planet, or even off-world, to gather their composure and reaffirm their loyalty to the Tau'va.
However, it was not until agents of the Inquisition were made aware of the region's influence that an arguably greater threat became known.
The indigenous flora and fauna within the region resemble in many ways those of surrounding regions, yet they have diverged physiologically and behaviourally in a quite drastic manner, becoming increasingly savage and predatory in ways that do not conform to evolutionary patterns known in the xenobiological lore of the Imperium.
The fact that these divergent species seem most concentrated in regions that are frequently used by the Stigmartus as landing and encampment sites suggest that they may be the result of an insidious and startlingly swift-acting Warp-taint brought to D'Shas'Ka by the servants of Chaos.
- Deathwatch: The Jericho Reach (RPG), pp. 69-71