"For almost six thousand years, we have stood strong against sedition, heresy and xenos domination, holding true to the light of the God-Emperor. For almost six thousand years, we have been alone in the darkness, a single beacon of light amidst the shadows of discord and depravity. No longer must we suffer so, no longer must we endure in silence… for we are reunited with our distant brothers, who return to deliver us from the shadows that have encroached upon this Sector for millennia! Praise the Emperor, and praise His valiant Crusaders!"
- —Lord Commander Ortana Lokk
Castobel is a Hive World within the Achilus Crusade's Orpheus Salient in the Jericho Reach. Regarded as the jewel of the Orpheus Salient, Castobel remained loyal to the Imperium through the Reach's "Age of Shadow" when the Imperium had lost control of the sector, and welcomed the Achilus Crusade with open arms, turning its resources to the support of the re-conquest of the former Jericho Sector.
The planet is a bustling, industrious Hive World, with a production capacity that eclipses that of every other world so far conquered by the crusade. The sheer numbers of people within Castobel's hive cities provide an ample supply of recruits for the Astra Militarum and Imperial Navy.
Castobel is a fine example of how Lord Militant Tiber Achilus envisioned the progression of his namesake crusade -- conquered worlds contributing to the conquest of others, forging a newly self-sufficient Jericho Sector with each victory.
In recent years, Castobel's fortunes have changed. With the arrival of Hive Fleet Dagon, Castobel has come under siege by the Great Devourer and a world once responsible for supplying a small but significant proportion of the crusade's troops and materiel has virtually shut down.
The Tyranid blockade and the invasion force on the ground has all but caused Castobel to grind to a halt, and its populace now huddles in fear of the ravenous beasts outside their walls.
However, all is not yet lost. Of all the worlds in the Orpheus Salient under assault by the Tyranids, Castobel may yet be freed of their menace. Castobel is barren and lifeless but for the masses in the four remaining hive cities, with little in the way of biomass resources for the Tyranids to consume.
Thanks to the decisive action of Lord Castellan Ortarna Lokk, an unsteady stalemate has arisen, with the Tyranids unable to gain ground and enough bio-mass to replenish expended forces quickly, stealing away their greatest advantage: seemingly limitless numbers.
With time and bloodshed, the Tyranid threat on Castobel could be ended, leaving a population hardened by war and eager to enact revenge upon the monsters that tried to destroy their home.
The planet's military is composed of the Castobel Planetary Defence Force (light infantry, equivalent to 44 regiments) commanded by Lord Castellan Ortarna Lokk, and an Astra Militarum garrison of 11 regiments commanded by Brigadier General Titus Korven.
Primary exports and tithed goods are basic munitions such as las weapons, solid projectile weapons, and ammunition, agricultural and mining equipment, and Astra Militarum regiments. The world's primary imports include fuel, food, potable water and raw materials for manufacturing.
"And the stars will be blotted out, and men shall despair saying that they are without light. And in that moment of heresy they doom themselves most surely."
- —From the sermons of Sebastian Thor
Castobel is ancient, with some historical evidence to suggest that it predates the Imperium, having been colonised by Humanity at some point during the Dark Age of Technology. In the days of the Great Crusade, Castobel joined the Imperium after a brief and bloody war eliminated its original ruling caste, which was swiftly replaced by a Planetary Governor installed by crusade forces.
When the Imperium first claimed Castobel in the 30th Millennium, it was already a prosperous Hive World, with four colossal cities emerging from the lifeless ash wastelands of a world dedicated to industry. Under Imperial rule it grew further, with several of the smaller wasteland settlements developing together into two additional hives by the middle of the 33rd Millennium, and gaining stewardship of Battlefleet Jericho's primary dockyard a few centuries later.
When the Jericho Sector collapsed into the anarchy of the "Age of Shadows," Castobel endeavoured to remain aloof from the disarray, remaining staunchly loyal to the God-Emperor in spite of the sector's collapse. Using what remained of the sector's fleets, including loyal remnants of Battlefleet Jericho, Castobel's Imperial Commander worked tirelessly to maintain the Emperor's law on several nearby worlds.
Still, the isolation took its toll on Castobel and its colonies, and the world could not remain as it once was. After centuries separated from the Imperium, the hive cities on Castobel had become virtually independent city-states, unified only by their common faith in the Emperor.
That faith was fought for more fiercely than almost any other facet of life on Castobel. Separated from the higher authorities of the Adeptus Ministorum, the ruling families of the six cities found common ground in the need to maintain the religious structure that had for so long defined Castobellan life.
The result was an organisation known as the "Aquilan Pluracy," which took the place of the old Castobel Diocese as the highest religious authority on the planet, maintaining the temples and ensuring the populace remained appropriately reverent towards the Emperor.
This state of affairs remained largely unchanged for several Terran millennia in spite of raids by aliens, Renegades and Heretics, until 789.M41, when Battlegroup Santos arrived at the edge of the system to be greeted by vessels that had once belonged to Battlefleet Jericho. Upon discovery of their kinship, a message was sent to Lord General Mikal Curas immediately, informing him that Castobel was loyal to the Imperium and wished to return to the fold.
A hundred days of celebration followed, and at the end of that time, the Astra Militarum regiment called the 1st Castobel Reborn was raised and sent forth to serve the Imperium, while Lord Commander Ortana Lokk of Hive Tyralos was selected to rule as Imperial Commander and Lord Castellan of Castobel.
By the end of that year, a further hundred regiments had been raised, with more on the way in every passing year. In the years since, over two thousand regiments of Castobel Reborn have been mustered and distributed across the Jericho Reach, alongside vast quantities of materiel.
That all changed, as so much in the Orpheus Salient did, when the Shadow in the Warp descended upon the Jericho Reach. Castobel came under assault in the early months of 817.M41, after more than four standard years of mounting interference within the Warp.
Once again isolated from the wider Imperium, Castobel's forces -- its planetary defence force and the three hundred Astra Militarum regiments mustered since 812.M41 but left stranded by increasingly difficult Warp travel -- immediately set about bolstering their homeworld's defences and preparing for the arrival of a monstrous aggressor.
The Tyranid onslaught was swift and terrible, and they managed to overrun Hive Trimalov within six solar weeks of the first bioforms making planetfall. Billions died, torn apart and devoured by mindless, slavering beasts and towering, malevolent monsters.
As the Tyranids destroyed Hive Trimalov and began to spread outwards to the other hives, Lord Castellan Lokk withdrew with his advisors to contemplate how best to defend against this enemy. When he returned after three solar days, he was grim and humourless, but stated that he knew what must be done.
While this occurred, the Tyranids had begun to move on Hive Tyralos, the second-most densely populated of Castobel's hive cities. Hundreds of thousands of troops -- both soldiers and civilians bearing simple weapons as ragtag militias -- stood in defence of Hive Tyralos as the evacuation began, selling their lives dearly to allow as many people to flee as possible.
Then the order came through: withdraw into the city, lure the Tyranids in. An hour later, the skies burned with crimson light as Hive Tyralos died in atomic fire, the incandescent fury of its ancient reactors and generators unleashed to obliterate the swarm.
Both sides now exist in an unsteady stalemate. Castobel's defensive forces are depleted, weary and demoralised, and epidemics of Tyranid-spawned maladies rage through the populace.
The Tyranids are similarly depleted in number and having been denied the biomass of Hive Tyralos -- both their own and that of its populace -- they cannot swiftly replenish their numbers nor easily muster the power for another assault. The war has settled into a routine of probing raids and attempted infiltrations of the remaining cities, with the defenders fearful of the skulking, hissing monsters that lurk outside their walls.
Yet hope, of a sort, remains. With the Tyranids starved of biomass and the reinforcements it would provide, the swarm is at its most vulnerable. If Castobel's defenders can deny the Tyranids long enough, the Tyranids might be crushed utterly, leaving the bio-ships in orbit starving. This hope is a distant one, but one that many are clinging to.
The Last Holdout
Unlike countless other worlds, Castobel remained loyal to the Imperium during the Age of Shadow, staying faithful to the Imperial Creed and maintaining the society that the Imperium had required of it when the Jericho Sector still existed.
Though more akin to independent city-states than cities on a united world, the hives of Castobel hold to the authority imposed by the Aquilan Pluracy, which rules in the name of the God-Emperor. Consequently, when the Achilus Crusade reached Castobel, it found a world that welcomed it with open arms and was able to provide vast quantities of troops and materiel. The world's survival is remarkable given the high external resource demands of a hive world, yet it had somehow managed to remain strong and loyal for thousands of years of isolation.
As the Jericho Sector fell to darkness and sedition, the loyal remnants of Battlefleet Jericho fell back to the orbital docks above Castobel, accompanying whatever Imperial merchant vessels they could gather. As a result, Castobel was, over the following months and years, able to dominate a cluster of mining colonies and Agri-worlds nearby, re-establishing a limited form of Imperial rule and keeping Castobel itself supplied with food and raw materials.
In conjunction with advanced and ancient food processing facilities within Castobel's hives -- which, upon the world's reclamation by the Imperium, became a subject of great interest for the Adeptus Mechanicus -- these facilities allowed Castobel to function in spite of its almost total isolation.
As the millennia passed, the six hives became increasingly divided from one another, feuding and even warring over the already limited resources, and soon, the number of starships at Castobel's call and the number of worlds supplying it began to dwindle.
Still, by the time Lord General Curas' forces reached Castobel, it was more than able to provide billions of tonnes of material and millions of soldiers to the ongoing war effort, and proved to be a turning point within the crusade, as the burden of supplying so vast an endeavour was no longer borne solely by worlds on the other side of the Jericho-Maw Warp Gate.
The Castobel Reborn
Upon Castobel's compliance, Departmento Munitorum surveyor companies descended upon the world to determine its capability to aid the Achilus Crusade. After a preliminary survey, lasting six solar months, it was declared that Castobel would be assigned the highest Tithe Grade, reflecting its massive capacity for supplying materiel and warriors alike.
A further declaration was issued that the world could produce as many as a hundred regiments of Imperial Guardsmen a year, each numbering as many as ten thousand troops, without unduly impeding its ability to produce munitions and machinery.
Having already produced the 1st Castobel Reborn as part of the world's celebration of renewed Imperial rule, Castobel produced its first tithe of a hundred regiments a year later. The first muster saw Lord Militant Solomon Tetrarchus himself in attendance, and he gave the first hundred Castobel regiments the name of "the Reborn" and the right to bear his own insignia on their banners, to honour the first regiments founded within the Jericho Sector for thousands of years.
Below are a number of significant locations across Castobel's surface.
One of Castobel's oldest and most populous hive cities, Tyralos predated the Imperium by several millennia, and contained a wealth of ancient technology dating back to the era of its original construction.
When the Jericho Sector still stood, Tyralos was home to a major Adeptus Mechanicus presence, containing a coven of archaeotechnologists eager to uncover the secrets of the technology hidden within the depths of the hive.
As the largest congregation of Tech-priests on Castobel, Tyralos' coven became the highest Adeptus Mechanicus authority on Castobel when the Age of Shadow descended upon the sector, granting the hive considerable power and leverage over the other cities.
The Cult of the Machine prospered within Hive Tyralos during its isolation, growing to challenge the Aquilan Pluracy within the city's depths.
When Castobel was reunited with the Imperium, so too were the coven's members reunited with their brother Tech-priests, and efforts to unlock the secrets of Castobel's ancient technology were renewed by the newly arrived Explorators.
Many secrets were passed back beyond the Well of Night to Forge Worlds far from the Jericho Reach, for detailed investigation by the Mechanicus. With the Tyranid invasion and the fall of Hive Trimalov, Hive Tyralos became the next most obvious target for the Tyranids.
At the height of the Tyranid attempt to overrun the hive, the Lord Castellan gave the order to sacrifice Tyralos to deny it to the enemy, an order met with much hostility from the Adeptus Mechanicus, who regarded the hive's contents as sacred.
After fierce debate that raged for solar days, the Tech-priests relented, under the condition that they would have a solar week to salvage what they could from the hive's depths and perform the correct rites to overload the hive's generatoria.
Hive Tyralos today is an irradiated ruin, barely resembling the towering city-complex it once was. As a testament to the fury of the city's destruction, the land a hundred kilometres in every direction around the city's ruins is irradiated and vitrified ash, utterly inhospitable to even the massively adaptable Tyranids.
Once the largest and most powerful of Castobel's hives, Trimalov is now utterly devoid of Human life for the first time in thousands of Terran years. Possessed of a populace of more than twenty billion souls and home to Castobel's grandest cathedral, Trimalov was, for millennia, the world's capital, ruling in the Emperor's name over the other five cities.
Trimalov was, as well as the political heart of Castobel, the centre of the world's religious life. The Castobellan Diocese was based within Trimalov's cathedral, an immense edifice of gleaming marble and stark obsidian capable of containing over a million worshipful servants of the Emperor and dominating the hive's central spire.
This cathedral grew in magnificence and opulence with every passing century, the tithes of the devout furnishing generations of Cardinals with the finest of goods. The cathedral's glory did not diminish during the Age of Shadow, thanks to the Aquilan Pluracy, which sprang from the long alliances between the state church and Castobel's ruling families. The Aquilan Pluracy saw the temples maintained and the people kept faithful through the long ages of isolation, ensuring that the world remained true to the Emperor's rule.
When the Imperium returned to Castobel, it was Trimalov's Lord Commander Ascendant who was made Imperial Commander and Lord Castellan of the entire world, elevating Trimalov once more to dominance over Castobel. However, the return of the Imperium was not as simple as some had believed it would be.
The Imperium had changed since the Jericho Reach fell, most notably in the form of the Ecclesiarchy. Castobel's priests found themselves proponents of a heretic religion, adhering to a creed cast out after a brutal War of Faith millennia after the Age of Shadow began.
The priests of the Adeptus Ministorum descended upon Castobel to find the Temple of the Saviour Emperor still holding sway over the people, and set about replacing it with a more modern creed based on the reforms of Sebastian Thor following the Reign of Blood, to the dismay of the Aquilan Pluracy.
Yet Trimalov is no more. It was torn open and infested by the Tyranid menace, its people butchered and devoured to feed their eternal hunger. The structure remains, a hollow shell standing in mockery of the long isolation Castobel endured.
Its form is corrupted by spore chimneys and spawning pits, and vile xenoflora writhes with a mindless malice for kilometres in every direction, bursting from the ash and entangling steel, basking in the atomic heat of the city's ancient generatoria.
One of the four remaining hive cities, Kevor was constructed after the Horus Heresy within the spine of a mountain range, burrowing deep into the crust and extending for almost two hundred kilometres across the peaks. Possibly the most securely located and heavily defended of the hive cities, Kevor's highest spire now serves to house the Lord Castellan and his command staff.
Hive Kevor grew out from a string of mining settlements running along the length of the Kevor Mountains, the hive taking the mountains' name as the settlements expanded into one another and spread further and further out from their humble origins. By the time the mines within the mountains had run dry, nearly twelve billion souls inhabited Kevor and the city had become an established part of the landscape.
While the mountains no longer contain the resources they once did, the self-sufficient and stoic attitude of Kevor's populace remained strong, and the city's primary trade soon turned from mining to warfare, with much of the population joining Kevor's militia or leaving the city to serve on Castobel's few remaining warships.
When the Imperium returned to Castobel, Hive Kevor provided over a third of the troops recruited into the Astra Militarum, eclipsing all but the colossal Hive Trimalov in the number of soldiers mustered.
At present, Kevor remains defiant of the Tyranids skulking through the ash-choked mountain passes and swarming through the skies above the city. Its populace accepted the realities of war more swiftly than any others on Castobel, and their fortified mountain-hive promises to be difficult for any foe to overcome, even the Tyranids.
A short, broad hive city spread across a vast expanse of ash desert, Hessax is the youngest and smallest of Castobel's hives, though still several thousand Terran years old and home to more than ten billion loyal servants of the Imperium.
Hessax's location, as distant from the other hives as possible, is tied inexplicably to its purpose. Intended to manufacture components with which to maintain the vessels of Battlefleet Jericho, Hessax's isolation was a deliberate security measure to limit access to starship parts of such rare quality.
With the coming of the Age of Shadow, Hessax's role became increasingly crucial, its forges serving to maintain the limited flotilla that supplied and protected Castobel and its colonies from outside aggression.
Production increased dramatically, for the hive city was the only place capable of providing the needed components to Castobel's makeshift fleet.
Since the return of the Imperium, Hessax has been no less busy. With only limited repair and resupply stations within the Jericho Reach, Lord Admiral Anastasia Arkelius proposed to take advantage of any supply routes that could be found.
In short order, Hessax's forges were turned to serving the Achilus Crusade's battlegroups. However, with the arrival of the Tyranids, fewer and fewer ships have been able to reach Castobel's orbit to resupply, and thus Hive Hessax stands dormant, its comparatively small size and isolation proving to be their best protection from the swarms of Hive Fleet Dagon.
Hive Orolan and Hive Ibellus
The two remaining hive cities on Castobel have long been regarded as a pair, rather than singly. Had the world continued to grow as it had done when the Jericho Sector still stood, they would likely have expanded into one another, becoming a single, massive hive rather than two distinct cities.
Situated less than fifty kilometres apart, the "twin hives" of Orolan and Ibellus are similar in many ways, their histories and populace intertwined by industry and tradition. Orolan has traditionally been dedicated to the refinement and processing of raw materials, while Ibellus contained many of Castobel's most prolific manufactories, turning those refined materials into machinery and munitions.
Largely untouched by the politics that defined life in Tyralos and Trimalov, few but the nobility in the twin hives saw much change when the Age of Shadow fell, save for variation in work schedules and shipment deadlines. Similarly, the return of the Imperium saw increased activity within Orolan and Ibellus, but little else of note until recently.
The situation changed in late 816.M41, mere solar months before the Tyranids arrived; slightly more than two companies of Blood Drinkers Space Marines arrived in Castobel orbit aboard the Battle Barge Crimson Sacrament, damaged in conflict with some monstrous enemy.
Several squads immediately made for Hive Hessax, seeking repairs and resupply from the forges there, while two full companies arrived in Hive Ibellus. Within weeks, the forces in Hessax had returned to orbit, but the 3rd and 4th Battle Companies that had come to Ibellus had spent the time fortifying the hive's tallest spire against an impending attack.
Whether the Crimson Sacrament departed Castobel entirely or if it fights against the Tyranid fleet is unknown, but no sign of the vessel has been seen since it left orbit.
The arrival of the Tyranids saw Orolan and Ibellus subject to brutal orbital bombardment from the orbiting bio-ships, followed by wave after wave of monstrous aggressors. While Ibellus stood firm thanks to the prowess and tenacity of the Blood Drinkers, Orolan suffered greatly.
Though it did not fall, thousands of warriors and millions of civilians were slain before the Tyranids could be driven back. The Blood Drinkers have remained within Ibellus, and much of the population of Orolan has retreated to the safety of their sister city and the Astartes who stand guard over it.
- Deathwatch: Core Rulebook (RPG), pg. 342
- Deathwatch: The Jericho Reach (RPG), pp. 120-123