Forge Castir is a Hell-Forge of the Dark Mechanicus, wholly dedicated to the Ruinous Powers, located in the Calixis Sector of the Segmentum Obscurus. This is one of three massive forge complexes located on the Chaos-controlled world known as The Hollows, one of the many strange worlds located amongst the so-called Gloaming Worlds on the outer ring of the Warp rift known as the Screaming Vortex. Forge Castir continues to wage an eternal war against the rival Hell-Forge complex known as Forge Polix.


"Torn asunder by war and united by hate. Twin Forges hammering out the chorus of battle, crafting talons of death upon brass wings. Lies, threats, contradictions, and half-truths are the local tongue. If the Hollows does not rip itself apart first, it is a lovely place to visit."

— Asrodel the Fated

Amongst the Gloaming Worlds on the outer ring of the Screaming Vortex, few worlds are as immediately recognisable as The Hollows. From the void, the planet seems oddly deserving of the name: like a dismembered corpse, only a little more than half a world spins in orbit. The upper hemisphere is mostly intact, crumbling remains spiralling outwards from the lower half where only a stem has been left behind. Like a rotten, half-eaten fruit cast into the stars, The Hollows is a world that could only exist within the reality-bending zone of a Warp Storm.


It was not always so -- once, when it was whole, this world bore the name Hellwhisper. Rich in natural resources, habitable by a wide array of biologies, and strategically located within the Vortex, Hellwhisper was a rich prize that drew the attention of a group of outcasts from the Tech-priests of Mars. Led by Arch-Magos Elikous, the Hereteks established three massive forge complexes on Hellwhisper and swiftly earned a reputation for producing large quantities of useful technology for the denizens of the Vortex. Elikous left two of the forges to his most brilliant protégés and locked himself away in the third forge, the largest and most advanced facility. There, Elikous focused his brilliant mind and prodigious technical skills upon a mysterious project of his own devising. No records remain to explain Elikous' obsession, but there are many whispered legends of what happened next. Most of the surviving accounts vary wildly in details and often contradict each other, but the most detailed of these records are the hololiths of Graz'tzar. According to those Leximechanics possessing the proper protocols to access such proscribed data, Graz'tzar was the first Prophitect of the Stygian Order.

Eternal War

The strange Dark Mechanicus-held world known as The Hollows upon which Forge Castir can be found

Whatever the true fate of Arch-Magos Elikous may have been, the survivors of both remaining forges wasted no time in declaring themselves the true heir to Elikous' legacy, triggering a struggle for control over the planet's abundant resources that has gone on for six standard centuries. Hellwhisper was carved up like a feast between the two warring forges, stripped of vast amounts of heavy metals, chemicals, and precious ores. Deep-core mining devoured huge amounts of the planet's lower hemisphere, depleting nearly half the world's total mass and beginning what was perhaps inevitable from the start. Hellwhisper was gone, and only The Hollows remained.

Now, the planet is consumed by the flames of war; armies of barely-trained menials equipped with bionic war-implants and shock-pikes clash with sophisticated Battle Servitors while orbital strikes lance down into formations of scuttling Velocireapers threatening the flanks of disciplined mechanical troops. The two Forges employ much more unusual forces as well, willing to utilise ludicrously destructive weapons, soldiers, and stratagems to settle their ancient grudge once and for all.

Although the conflict still grinds on, over the last solar decade the advantage has been grasped by the forces of the Exospectre, the undisputed master of Forge Castir, who now holds the upper hand on The Hollows. While the armies of Forge Polix still control vital areas of The Hollows -- such as the Forgeflow and Mechmoor -- they have slowly been forced back into a defensive posture. Any significant change in this bitter conflict is likely to be wrought from without rather than within -- a fact that has not escaped the two rival Dark Magi, who even now seek for allies and mercenaries to support their bid for absolute domination of The Hollows.

Both Magos Onuris and the Exospectre are constantly focused on the war between them, but both would also be greatly interested in tipping the balance of power by gaining an advantage in technology or allies. The Exospectre has already located and plundered a Necron tomb, claiming its technology for his own uses. This act has spurred Magos Onuris to try to establish contact with Necron forces in the Screaming Vortex, hoping to locate a Necron Lord with whom he can bargain for assistance against his hated foe.

Forge Castir

Surrounded by acres of ruined scrap metal and wrecked debris of countless machines, Forge Castir rises like a rust-red mountain many Terran miles above the ground. The Forge belches forth a volcanic plume of toxic gases from the many smelters and manufactoria within. Outside, long, twisting arteries of mag-rails convey raw materials into the forge and sophisticated technology out to far-flung outposts and sub-forges.

A spiderwebbed maze-like system of corridors -- lined with pipes, sparking wires, valves and turning cogs -- connects the various areas of Forge Castir. Each level is divided into a series of chambers containing individual works in progress. Each item crafted by Forge Castir is an individual, unique piece -- many of them masterwork examples of their kind. More than a few items held in chambers near the apex of the forge incorporate various xenos technology and systems, but only a bare handful have anything to do with the energies of the Warp. It is not uncommon to find alien traders rubbing shoulders with Chaos Space Marines and would-be Champions of the Dark Gods, all seeking a particular weapon or item custom-made from the depths of Forge Castir.

The very highest level is crammed with humming Cogitators, lovingly maintained by a hand-tuned host of Servitors. These Cogitators are purpose-built with specific data-matrices to collect and study individual Machine Spirits, assigning different areas to catalogue and segregate them by complex occult formulae. Some Hereteks whisper that entirely new Machine Spirits are crafted in the upper levels of Forge Castir, synthesised from the forced combinations of the strongest, most aggressive, or most insane of Machine Spirits that the forge has carefully selected for such traits. These gene-locked infotombs and data-transepts are engraved with minute lines of binary micro-runes and charms to ward off unauthorised access. However, from time to time, a memory cloud of suppressed data escapes even these precautions and infects Servitors and Hereteks alike until it is brutally expunged by the Excrucimancers.

Notable Forge Castir Personnel

  • Exospectre - The Exospectre is the undisputed master of Forge Castir, self-proclaimed heir to Hellwhisper, and -- for the present -- pre-eminent Arch-Heretek of The Hollows. The Exospectre is a name that rings with dread and glory in equal measure across many of the Gloaming Worlds. The Exospectre has no other name that is known within the Screaming Vortex, but rumours and conjecture of his origins are nearly ubiquitous throughout the Gloaming Worlds. In appearance, he is a towering figure over two metres in height, his bulky form concealed by layers of mouldering, ragged robes that swathe him from head to toe. A host of slithering Mechadendrites are all the limbs he requires, and the susurrus of oiled metallic scales accompanies his every move. Eccentric even by the standards of Hereteks, the Exospectre does not normally speak, preferring instead to plug one of his Mechadendrites into a number of Servitors specially-modified to issue his commands. Some agents of the Inquisition have claimed that the Exospectre possesses multiple bodies, each kept in its own stasis chamber connected to a transmat altar. Despite his formidable reputation, many Hereteks seek out the Hollows in order to apprentice themselves to the Exospectre and learn what they can of his secrets. The style of technology within Forge Castir is a product of the Exospectre's genius intellect and desire for precision-crafted individual works; nearly all of the technology he personally oversees requires vast amounts of resources and time due to his search for perfection in every rivet, cog, and node. Amongst the Exospectre's finest creations are the Aposticators, the Tech-Assassins and their Velocireaper hunting packs, the Prophitects, and the Excrucimancers.

Castrian Specialised Units

  • Aposticator - The Exospectre does not tolerate failure. Although many Hereteks seek him out to learn his secrets and labour in his forge as a path to greatness, many more scheme against him to serve their own ambition. Those Hereteks who anger the Exospectre are taken away by masked Excrucimancers into the deepest chambers of Forge Castir to be transformed into hideous conglomerate beasts known as Aposticators. An Aposticator is a writhing mass of mechadendrites many times longer than a man's height. At the creature's apex is a spheroid conglomeration of bionics formed from the heads of those Hereteks unfortunate enough to earn the Exospectre's wrath. These heads are welded together and wired into one singular -- and quite insane -- consciousness. Conditioned using stolen xenos torture devices into absolute and unquestioning loyalty, Aposticators serve the Exospectre as guardians, patrollers, and shock troops in the low-gravity conditions of The Hollows' Stem, where they stride or hover across the ruined setting. From time to time, the Exospectre despatches Aposticators to serve as interim commanders for Forge Castir before a more permanent leader is sent. Even veteran Castrian maniples are uneasy at serving under Aposticators, the eerie, harmonically-distorted gestalt voice of the sundered Hereteks making up its body hardly inspiring confidence under the best of conditions.

Notable Castrian Technology

  • Castrian Soul Cage - Known throughout the Screaming Vortex for their expertise in the construction of Daemon Engines, the Dark Magi of Forge Castir have created a truly disturbing device -- the Castirian Soul Cage -- that they use to trap and hold daemonic entities before they are bound to their new metal prison. A Heretic can use a Cage as part of any ritual in which his intent is to summon a daemon. This can include summoning a daemon that will eventually inhabit a Daemon Weapon or Daemon Engine, or even a ritual that is used to summon a daemon directly into the material realm. At the end of the ritual the daemon will be contained within the Soul Cage as long as the Heretic that trapped the daemon is able to maintain control. A trapped daemon can be freed intentionally and the Soul Cage can be used to channel the daemon towards its original purpose (such as creating a Daemon Weapon). Those Heretics who use the Soul Cage need to exercise caution, however, as daemons tend not to like being imprisoned against their will.

The Hollow Blades, a Castir Lightning Khopesh to the left, the Polix Heavy Khopesh to the right

  • The Hollow Blades - One of the more famous weapon designs of the Vortex are the Hollow Blades, a common name given to a pair of curved swords -- one made by Forge Polix, the other by Forge Castir. The blades are so well regarded that the Heretic Astartes of the Traitor Legions have been known to seek them out, and the warriors of the Thousand Sons have a particular affinity for the peculiar, sickle-like shape the blades take.
    • Castir Lightning Khopesh - Almost the complete opposite of their heavier counterparts from Forge Polix, the Hollow Blades of Forge Castir are designed as fast and agile duelling weapons. Often used in pairs, these elegant blades feature bowed handles that allow them to be spun and turned in the hand with very little effort. The thinness of the blades also makes them difficult to defend against, and their only true match in combat are the Polix Hollow Blades.


  • Black Crusade: The Tome of Fate (RPG), pp. 36, 39, 41, 84-85, 88-89, 92
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