Dark Angels - Chapter Headquarters: The ruins of Caliban are located in the Cadian Sector, to the galactic north of the Eye of Terror. Prior to the Great Crusade and the Horus Heresy, the Death World of Caliban was covered with lush forests, inhabited by monstrous creatures warped by the proximity of Chaos in the Eye of Terror. The Humans of the planet were a proud, martial people, forced to live in great stone fortress-monasteries.The Dark Angels eventually rebuilt their fortress-monastery on the asteroid that had borne the original fortress-monastery of The Order, known as Aldurukh, "the Rock of Eternity" in one of the old Calibanite dialects of Low Gothic. Aldurukh was originally the name of the mountain that The Order's founders had decided on the site to build their fortress-monastery, using the name of the mountain for the fortress.Though The Order had other fortress-monasteries, Aldurukh was their first, and so they gave it a name that mattered, a name that summed up exactly what they were trying to build. This sacred site was The Order's literal rock, their foundation of stone. As long as it endured, then some part of their ideals would always be alive.The Dark Angels drilled deep into the old bedrock and rebuilt the ruins into a vast new complex with advanced Imperial technology worthy of a Chapter of Astartes. The fortress-monastery is known officially as Angelicasta ("the Tower of Angels") but is more commonly referred to as "The Rock" just like its ancient predecessor Aldurukh, though this term is more properly applied to the dead asteroid that is all that remains of lost Caliban.Following the destruction of Caliban, the Dark Angels made The Rock their new home. Never was there a gloomier site, for although the Warp Storm that scoured Caliban could not penetrate the fortress-monastery of Aldurukh's shields, they left an indelible mark.The force field over the fortress-monastery held, but was rent with cracks. To this day, there exists a disturbance within the field's protective shell, as if part of that tempest still rages within. Great chain-lightning arcs across the artificial atmosphere that surrounds the craggy Rock, briefly outlining the ruins that crown the asteroid.The Dark Angels explored the halls and dungeons that they found beneath the fortress-monastery. There, they claimed the hoard of machinery that had sat untouched since the little-understood Age of Technology. Many of the devices from that apex period of Human invention still worked, like the great shield generator itself, although their mechanisms were now unfathomable.Although the extant halls were large, a massive labour carved out deeper and deeper catacombs beneath the asteroid's bedrock, excavating room for an entire Space Marine Legion. With the aid of the Tech-priests of Mars, docks were added, allowing for the entrance of spacecraft. Although it took centuries to complete, The Rock was also outfitted with Warp-Drive engines, allowing the Dark Angels' new headquarters to travel across the galaxy through the tides of the Immaterium.While the artisans did marvellous work, crafting halls full of clustered columns rising to arched vaults, and much decorated ceremonial crypts to hold the Ist Legion's sacred relics, it was a grim place, full of echoes and cold stone.Although only a fraction of what was once Caliban, The Rock is larger than even the heaviest class of starship, and it bears formidable firepower. The sheer sides of its mass are studded with gun turrets, Lance batteries, torpedo tubes, observation blisters and communications relays. Its cavernous docking bays can accommodate many hundreds of smaller craft -- including Thunderhawk gunships, Nephilim Jetfighters and even Escort frigates.No effort was made to rebuild the ruined Tower of Angels atop The Rock, and even now it remains undisturbed and eerily silent, protected from the cold depths of space by the same force fields that shrouded it from the destruction of Caliban. Although attempts have been made to mask it, an unusual energy signature emanates outwards from The Rock, portending of some great power hidden within.Beneath the shattered ruins, many dark secrets lay cloistered from sight, and the deeper into The Rock's labyrinth of dungeons one goes, the closer one comes to the truth of the Dark Angels -- even truths they themselves do not yet comprehend.The warrens beneath The Rock are where the Dark Angels bring their Fallen Angels brethren to be redeemed by their Interrogator-Chaplains. It is believed by the Inquisition to hold many other secrets of critical importance to the Imperium.Only when a Dark Angel reaches the rank of Master (Company Captain) does he truly learn all the secrets of the Dark Angels, but one secret is known only to the Supreme Grand Master, the Master of the Chapter: the Fallen Angels' leader, the Chaos Champion Luther, is not only still alive, but imprisoned within the deepest, most secure cavern of The Rock.He is incurably insane, and has thwarted the attempts of every Supreme Grand Master to make him repent to date. Luther simply rants and raves that he has no need of confession or repentance, for one day Lion El'Jonson will return and forgive him for his sins against the Emperor.Near the heart of The Rock lies a single cell. It is deep in the bowels of the asteroid base, where only the Watchers in the Dark and the Supreme Grand Master of the Chapter are allowed to venture. There, past locked gates that are shielded by dozens of feet of adamantium plating, is an oubliette.Its walls are inscribed with the most potent runes of warding known to Men, and they have been inscribed to keep creatures out, but also to keep something within. There, sustained in life for ten thousand standard years by a powerful stasis field, languishes the broken man who was once Luther.Luther's cell can only be reached by the Supreme Grand Master of the Chapter, who possesses the ancient Power Sword and mark of his office known as the Sword of Secrets. Fitting the blade into a cleft in the wall unlocks the iron gate leading to a dark tunnel and the rune-protected cell in which the Arch-heretic Luther is imprisoned.For nearly 10,000 standard years, the Dark Angels have kept the secret of the disastrous events that took place on Caliban at the end of the Horus Heresy. They will never reveal the truth to anyone outside their Chapter, for they could not bear for others to know their terrible shame.And all the while, deep within The Rock, his continued existence known only to the Watchers in the Dark and the Chapter's Supreme Grand Master, the Archtraitor Luther raves on -- speaking of what is to come or emitting senseless shrieks of despair.At times, his voice assumes a grating, inhuman quality and it tells cunning lies or speaks words of such utter despair that to hear them is to wish for death. It is the rare moments of lucidity, when Luther begs for his own end, that are, perhaps, the hardest to endure -- although each and every Supreme Grand Master has done so. Down the ages, the Supreme Grand Masters have had some success in using Luther as an oracle. Although his Warp-contaminated and deranged mind often wanders or attempts to deceive, during moments of lucidity the Luther-thing speaks of events that will be, or might be, or drops hints at what is hidden and where.Since the Fall of Caliban, each Supreme Grand Master has, in turn, taken the long, dark walk down to the heavily psi-warded cell. Each has tried to extract a confession from the Arch-heretic, each has tried to penetrate the madness that now clouds his mind; none have succeeded. The thing that was, and may still be, Luther has divulged many secrets -- from the names and locations of members of the Fallen; to the whereabouts of relics from the Ist Legion secreted in the underworks beneath the old fortress-monastery.Mostly, however, all that can be gotten out of Luther are mad ravings -- over and over he repeats that he has no need of repentance, for one day Lion El-Jonson will return and absolve him of his sins, and he claims that day is near and that he can already feel that the Lion lies close at hand. Yet the Supreme Grand Masters still hope to gain wisdom from this Dark Oracle, hoping to hear Luther recant, so that he might be, at last, released from the torments of life.Luther was recently freed from his prison during an unexpected attack of daemons on The Rock after the birth of the Great Rift and the end of the Noctis Aeterna that was led by the Fallen Angel Daemon Prince Marbas. The Dark Angels believed the attack to have little purpose other than mayhem and destruction, but Supreme Grand Master Azrael knows the truth. The attack was intended to provide a diversion so Luther could be freed from his millennia-long captivity. Luther's current whereabouts are unknown.Yet even the highest-ranking Dark Angels do not know everything, although they believe that they do... Buried yet deeper within The Rock, hidden in its innermost chamber, is the final, greatest secret of the Dark Angels and the Unforgiven. It remains unknown to the Inquisition or the Inner Circle of the Chapter. Only one person in the galaxy knows the full truth -- the Emperor of Mankind. Even in His living death upon the Golden Throne, even though the sunken orbits of his skull no longer have eyes, the Emperor still sees much.Hidden inside a secluded chamber at the heart of what was once the planet of Caliban, unreachable by all save the cryptic Watchers in the Dark, the Primarch Lion El'Jonson lies sleeping. There he slumbers, his wounds long-healed, waiting for that time when he will be needed again, when the clarion call of battle sounds for the last time, summoning him once again to defend the Imperium of Man against its many enemies.During his duel with Luther on Caliban, Lion El'Jonson suffered a severe psychic blow which left him mortally wounded. He was then pulled into the Warp and lost as the Dark Angels of that time believed. Yet what they did not know was that Jonson emerged from the Warp not long after on The Rock, his own abilities as a primarch having proven to be enough of a defence to prevent the Ruinous Powers from seizing him, though he had lapsed into a coma.Once Luther was taken prisoner by the Dark Angels, the comatose form of Jonson was also taken into the deepest chamber of the Rock and placed into stasis to keep him alive. It was the mysterious Watchers in the Dark, their purposes always their own, who led the wounded primarch to his rest deep within the heart of The Rock.Yet some amongst the Unforgiven believe the Lion will eventually return for one final crusade intended to lead the Dark Angels to their greatest victory for Mankind and finally bring justice to the remaining Fallen Angels. Others believe that the Lion will only return when the End Times come and the Imperium stands at the brink of destruction.For these believers, Jonson will reappear from the Immaterium, forgive the sins of the Fallen and reunite them with the rest of the Unforgiven as they prepare to defend Mankind one final time. Little do they realise that their primarch rests literally beneath their feet.