The six Blackstone Fortresses were discovered early in the Imperium's history, scattered across the void. Seemingly ancient even at that time, the dormant structures were cyclopean in scale and utterly mysterious. No sign could be found of those who constructed them. Despite exhaustive attempts at analysis, none could determine the nature of the super-hardened, onyx-like metals from which they were constructed.
The early Imperium ultimately claimed the Blackstone Fortresses for its own. Even dormant, the enormous battle stations made for exceptional deep-space naval bases. Towed into position by pilot craft, and encrusted with secondary Imperial structures, the Blackstone Fortresses became cornerstones of Imperial naval might.
It was during the horrors of the Gothic War -- the twelfth of Abaddon the Despoiler's notorious Black Crusades -- that the Blackstone Fortresses were awoken and their hidden capabilities as weapons of mass destruction made manifest. None know how the Despoiler came by the fell lore required to bring the Blackstone Fortresses' systems to life, but as the Gothic War ground on, it became clear that Abaddon's primary objective was to seize as many of these titanic weapons platforms from the Imperium as he could.
By the end of that tumultuous naval conﬂict, several fortresses were in the hands of the Black Legion, and at least one more had been destroyed. It was one of these legendary battle stations that was secretly given as a gift by the Despoiler to Huron Blackheart, the Chaos Lord of the Red Corsairs, in the wake of his rebellion against the Imperium during the Badab War.
Such a kingly offering not only bought the loyalty of the Red Corsairs for Abaddon's great galactic endeavour to claim Terra in the 13th Black Crusade in 999.M41, but also demonstrated the sheer incredible might of the Despoiler. After all, a warlord who could afford to give away even one such preeminent superweapon must be supremely confident in their own power.
To capitalise on the Necron and their C'tan masters' vulnerability to Warp-based attacks during the War in Heaven, the fortresses were equipped with a Warp Cannon that could create a devastating rip in the fabric of realspace that would unleash an eruption of psychic energy from the Immaterium powerful enough to destroy entire star systems. This power can be linked with the other fortresses to create an even more powerful beam, as became clear when Abaddon used two of the Fortresses to destroy the planet Fularis II, and three to cause the Tarantis star to go supernova during the Gothic War.
The Blackstone Fortresses have since fallen into the hands of both the Imperium and Chaos, and have influenced the outcomes of two of the most recent Black Crusades of Chaos against the Imperium. One of these massive battle stations, the Will of Eternity, was used by the Despoiler as an artificial meteor to destroy the defences of the Fortress World of Cadia in a massive kinetic strike at the height of the 13th Black Crusade after it had been disabled by the Imperial Fists' star fortress Phalanx.
The Blackstone Fortresses were a collection of six massive and mysterious artefacts of pre-Imperial alien culture that were scattered across the Gothic Sector in the Segmentum Obscurus. Each was a vast installation whose mass was larger than even the mightiest Imperial starforts and Segmentum Fortresses. Some Imperial archaeo-historians place the construction of these ancient artefacts anywhere between 17,000 and 300,000 standard years before their discovery in the 33rd Millennium. Other Imperial scholars disagree, estimating them to be far older, dating back to the early years of sentient life in the galaxy many millions of Terran years ago.
For as long as the Imperium was aware of their existence, the Blackstone Fortresses lay in a dormant state, with all but passive power systems shut down despite the best efforts to revive them. Although inactive, there was enough residual power in the fortresses' power grids to allow humans to live in them and turn them into powerful space-based, fortified hardpoints that were central to the stellar fortifications in the star systems they occupied.
The Blackstone Fortresses became the foundation of the Imperial Navy's strategy and presence in the Gothic Sector. With the exception of Port Maw, each sub-sector was based upon the location of a Blackstone Fortress, which functioned as the primary naval base for the sub-sector. Although almost entirely dormant, a Blackstone Fortress was still open to exploitation by Imperial forces. The Adeptus Mechanicus linked numerous weapon systems to its alien and near-incomprehensible energy grid, opened up vast chambers to be used as attack craft launch bays and installed defence turrets over its surface.
Gothic War (12th Black Crusade)
Three Blackstone Fortresses combining the power of their Warp Cannons to destroy the Tarantis System's star during the Gothic War Abaddon the Despoiler first learned of the existence of the Blackstone Fortresses and their potential power at some point in the 40th Millennium. Abaddon was guided by the visions of Zaraphiston to an Aeldari Crone World in the Eye of Terror. In the ruins of an ancient Wraithbone city littered with skeletons, the Sorcerer lead the Warmaster of Chaos to a room where a tapestry of flayed skin covered the walls from floor to ceiling. Upon its surface Abaddon read a prophecy -- the Penumbra Prophecy -- that revealed the secrets of six weapons of immense power. He immediately set out to learn how to gain control of these weapons, the six Blackstone Fortresses.
During the Gothic War, Abaddon was influenced by the crone Moriana, a former confidante of the Emperor Himself whose attempt to resurrect His physical form after the Horus Heresy had led her into damnation -- and who may have been a disguise of the C'tan known as the Deceiver -- to hunt down a pair of ancient alien artefacts. These devices, known as the Hand of Darkness and the Eye of Night, were present in the Gothic Sector and were capable of re-activating the massive xenos battle stations, bringing them under the Despoiler's control.
Thought impregnable by the Imperial Navy, the Blackstone Fortresses were overcome by Abaddon using a previously undiscovered method of shutting down the power supply, thus rendering all the weapons and defence turrets useless. Deactivated, the Blackstone Fortresses proved defenceless against ranged attacks and vulnerable against a determined boarding action. Once under the Despoiler's control, the Blackstone Fortresses were able to shed their grafted-on Imperial equipment and glide slowly through space under their own power, using their original Warp Cannon in place of the turrets and fighter bays the Imperial Navy had built onto them as defensive measures.
There is also a record of a boarding party comprised of Imperial Navy and Angels of Redemption personnel that made its way into one of the activated fortresses and described it as being like a living thing, pulsing with power. As the war progressed and Abaddon acquired three more of the fortresses, he was able to combine their Warp Cannon attacks to obliterate worlds and stars.
At the end of the Gothic War, the fortresses were attacked by a vast fleet of Imperials and Aeldari over the world of Schindelgheist, and Abaddon retreated into the Eye of Terror with two activated Blackstones, while the remaining Blackstone Fortress in his possession was re-captured. When the aforementioned boarding party boarded the Blackstone Fortress, the remaining three in Imperial custody simultaneously disintegrated.
13th Black Crusade
The colossal Blackstone Fortresses represented a pinnacle of technology never since equalled by Mankind. Six such artefacts were discovered scattered across the Gothic Sector, and it was there that the Imperium pressed them into service. Though the Adeptus Mechanicus only unlocked a fraction of the Blackstones' potential, that fraction was more than sufficient to see them employed as naval fortifications of frightening power. During Abaddon's 12th Black Crusade, the Gothic War, four of the six Blackstones were destroyed, but not before the Imperium suffered first-hand the effects of the fortresses' innate Warp-fuelled weaponry.
A single Blackstone had the power to obliterate a planet; three working in concert possessed the raw might to destroy a star. Thus perished the Taranis System, its defenders slaughtered just as surely as if by a blow from the Dark Gods themselves. The two remaining Blackstones were seized by the Despoiler and twisted to fulfill his own objectives.
Indeed, surviving reports indicate that one of the Blackstones that appeared in the Cadia System during the initial phase of the 13th Black Crusade was inhabited and controlled by a daemonic presence of a magnitude far greater than anything yet encountered. Unreliable accounts state that Blackstone Fortress was destroyed or driven off, while the Will of Eternity, the remaining Blackstone Fortress in Abaddon's hands at Cadia, was hurled down onto its surface, destroying that Fortress World and winning access to the Cadian Gate for the Forces of Chaos.
The Blackstone Fortress gifted by Abaddon the Despoiler to earn the support of the Red Corsairs of Huron Blackheartafter the Gothic War was later used to imprison the resurrected Primarch Roboute Guilliman and his followers when they were captured by the forces of Kairos Fateweaver during the Terran Crusade.
It became the site of fierce fighting between the Primarch's troops and the Forces of Chaos when the Fallen AngelCypher and the Harlequin Shadowseer Sylandri Veilwalker freed Guilliman and his remaining forces and led them into the interior of the fortress where a gate into the Webway allowed the Imperials to escape.
The Seventh Blackstone
As mentioned above, during Abaddon's 12th Black Crusade, the Gothic War, all six known Blackstone Fortresses controlled by the Imperium were lost, with two captured by the servants of Chaos and four destroyed utterly. Both captured fortresses would prove devastating during the early engagements of the 13th Black Crusade -- one traded away to secure the services of the legendary Renegade Huron Blackheart, while the other was eventually hurled into the surface of Cadia, resulting in Warp Storms and physical devastation that utterly obliterated the planet.
And for a time, that was the end of the story of the Blackstones.
But the galaxy is a vast and lonely place. For every sector abuzz with life, there are countless more that are dead zones. Even as wars reach into every corner of the galaxy, great swathes still lie silent, untouched and empty.
It was in one such silent sector in the galactic west that a new, seventh Blackstone Fortress appeared. In the furthest reaches of the Segmentum Pacificus, it sits amid a graveyard of starships that stretches more than a million miles across. This latest Blackstone Fortress is a key tactical asset for any who might suborn it to their will. Even a single one of these star fortresses can turn the tide of the most apocalyptic space battles, armed with weapons of unparalleled power.
The Blackstone Fortress is more than just a weapon, however, it is a cache of archeotech and artefacts from bygone ages. Relics of countless species lie abandoned in its halls -- a technological treasure trove that would prove utterly irresistible for any who seek to collect, study or leverage technology in their wars. It is for this reason that countless explorers of many different species and factions have gathered at the ramshackle void station called the Precipice. From there, they launch expeditions into the interior of the newfound Blackstone Fortress.
But unlike any of the other Blackstone Fortresses found before, this citadel is not inert, but seems to act, and even react, of its own accord. What this means is one of the most puzzling aspects of this Blackstone Fortress.
More mysterious still are the "hidden vaults." None can say what lies within -- but given the other secrets possessed by the fortress, the treasures inside must be priceless -- and many factions from across the galaxy have already begun to converge on the newest Blackstone in an attempt to seize its secrets.
Viewed from the top, the shape of an activated Blackstone Fortress has warped to resemble the eight-pointed Star of Chaos Undivided.
In terms of capability and technology the Blackstone Fortresses beggared belief -- able to glide sedately through the void with no obvious means of Newtonian propulsion and seemingly able to ignore the laws of inertia, their shielding and armour several times more potent than that of the greatest Battleship, while their weaponry harnessed Warp technology to unleash a beam of purest Immaterium with the power to obliterate any capital ship at extreme range in a single volley.
Even more terrible, the capabilities of the Blackstone Fortresses could be combined with one another to produce more potent Warp-based effects. Two Blackstone Fortresses could strip a world of its biosphere in an eyeblink, and three could destabilise a star. At the heart of every Blackstone Fortress, as was discovered by the Primarch Roboute Guillimanduring his capture and imprisonment aboard a fortress controlled by the Red Corsairs in the Maelstrom in 999.M41, was an ancient and massive portal to the Webway.
The pathways it led into were huge arterial routes that even starships could navigate -- they could accommodate the Imperial war machines of the Terran Crusade with ease. The innermost chamber of a Blackstone Fortress was vast, easily a hundred Terran miles across. Both its ceiling and its ﬂoor were lost in shadow. A titanic black column rose at the chamber's centre.
Out from that column, like the distorted branches of some dark arboreal deity, radiated hundreds of bridges, stairways, platforms and gantries. Countless dark doorways opened onto the Blackstone Fortress' heart, huge portals that seemed wrought for giants while the soaring bridges connecting the central column to the rest of the fortress were wide enough for Imperial Titans to cross.
The Blackstone Fortresses possessed some form of innate artificial intelligence and an arcane sensor system. For instance, when danger threatened in the vicinity of a Blackstone Fortress, ﬂashes of pale green luminescence danced along its darkened corridors, the ancient structure using this display of light to warn its denizens of the approaching danger.
Though the identity of the builders of these technical marvels remains a mystery, it has been suggested by certain Imperial savants that they were constructed by the Old Ones or the Aeldari for use in their ancient war with the Necrons. Indeed they are obliquely mentioned in Aeldari Mythology as the "Talismans of Vaul," objects of great fear and revulsion. Yet the Blackstone Fortresses also exhibited advanced technology, such as Void Shielding and apparently inertia-less propulsion, that was very different from that used by the present-day Aeldari. The power of the Blackstone Fortresses' Warp Cannons far surpassed even that of the Aeldari, the acknowledged masters of Warp-based technology in the galaxy.
Similarly, while the Blackstone Fortresses exhibit some aspects eerily similar to Necron technology in both function and appearance, they were also puzzlingly different in their use of potent Void Shields and their direct manipulation and utilisation of Warp energy, something that the Necrons' one-time C'tan masters regarded as anathema. Further detracting from this theory is the fact that there is some evidence that the manipulations of the enigmatic C'tan known as The Deceiver set the Gothic War in motion to ensure the scattering and/or destruction of these artefacts. It is also worth noting that whatever and whomever caused the destruction of four of the Blackstone Fortresses at the close of the Gothic War must have done so consciously and it was Inquisitor Lord Horst's belief that someone or something had deemed them too great a threat to continue to exist.
Finally, it is worth noting that the Blackstone Fortresses seem in most respects similar to the unspeakably ancient and mysterious Fortress Worlds of the Sabbat Worlds Sector, which are known to have been used by successive intelligent species as strategic military bases for eight million standard years in much the same way as the Blackstone Fortresses were used by the Imperium.
Taken together, these facts suggest that the Blackstone Fortresses are but remnants of an ancient and technologically advanced species scattered across the galaxy. As the capabilities of the fortresses make them ideally suited to do battle with the Necrons, it is reasonable to suspect that they are yet another leftover from that primordial conflict between the Old Ones and the C'tan, although given the dates for construction that Imperial experts attached to them and similar structures, it is equally likely that such an apparent connection is merely illusory and their origins are not directly related to that conflict. If this is the case, it suggests the existence at some point of a vast and previously unknown empire of a very technologically-advanced species.
If Imperial estimates are incorrect and the Blackstone Fortresses are in fact relics of that bygone age of conflict at the dawn of galactic history, then their most likely architects may be the Old Ones themselves, who were said to command the Warp in ways that their successors could only dream of. They may be the remnants of that species' defence against the original Necron advance during the War in Heaven. If the Aeldari myth-history of their gods is, in fact, a distortion and amalgamation of their race-memories of the Old Ones and the actions of the psychic beings which came into being through Aeldari faith, perhaps the Blackstone Fortresses are equated with the story of the 100 Swords of Vaul, the Aeldari Smith God, forged for the bloody-handed War God Khaine. This would mean that the actual weapons forged in ancient times by the Old Ones informed the subsequent myth of the Aeldari War in Heaven.
Known Blackstone Fortresses
- Will of Eternity - The Will of Eternity was the Blackstone Fortress deployed by Abaddon the Despoiler during the final phase of the 13th Black Crusade against the Fortress World of Cadia. Destroyed by the Imperial Fists' mobile star fortress Phalanx before its Warp Cannon could be used to eliminate all life on Cadia, the Despoiler turned even the Fortress' floating corpse into a weapon. Its massive remains were flung from orbit onto the surface of Cadia as an artificial meteor, its kinetic impact killing most of Cadia's remaining defenders and at last allowing the Eye of Terror to swallow the world. The geothermal stress caused by the Fortress' impact ultimately caused Cadia to rip itself apart. With Cadia and its black pylons destroyed, the Eye of Terror began to expand across the galaxy even as Abaddon at last realised his dream of seizing the Cadian Gate for the Forces of Chaos. With the first goal of the 13th Black Crusade achieved, Abaddon next turned to launching an assault upon Terra itself.