Manachean War

Manachean War Sons of Horus forces during the capture of Port Maw Conflict Horus Heresy Date 006-008.M31 Location Coronid Deeps Outcome Stalemate Combatants Imperium Traitors Commanders Grand Admiral Ospheus LaBray Lord Marshal Ireton MaSade Governor Malthus Grange Governor Pryamus Beket Iron Father Autek Mor Warmaster Horus Lupercal Primarch Mortarion Archmagos Draykavac First Captain Ezekyle Abaddon Taloc Thorne Autilon Skorr Strength 3,800,000 Solar Auxilia troops Imperial Army troops Imperial Armada ships Knights Loyalist Adeptus Mechanicus Iron Hands Raven Guard Imperial Fists Blood Angels Salamanders Death Eagles Sons of Horus Death Guard Night Lords Alpha Legion Iron Warriors Dark Mechanicum Knights Casualties Unknown, heavy Unknown, heavy

The Manachean War was a campaign of the Horus Heresy waged between 006 and 008.M31. Led personally by Warmaster Horus himself initially, the traitor lord sought to conquer the valuable industrial sectors of the Coronid Deeps.^[1a]

The Cyclops Cluster

Map of the Coronid Deeps

The attack on the Coronid Deeps would begin at the Cyclops Cluster, first taking the world of Gethsamaine followed by Dark Mechanicus ambassadors convincing the Forge World of M'Pandex to join Horus' cause. However on the Forge World of Mezoa the ruling Tech-priests judged the traitor Mechanicum ambassadors to be Hereteks, forcing Horus to blockade the planet.^[1b]

Letting Mezoa sit and rot in its isolation, the Warmaster began with the next stage of his plan. He dispatched the Death Guard led by Mortarion across the Cyclops cluster, where they captured the worlds of Lascal and Dominica Minor with the help of the Traitor Knights of House Makabius.^[1b] At Lascal, the Death Guard massacred the local Loyalist defenders, including Iron Hands remnants belonging to Clan Felg.^[1e]

The Manachean Commonwealth

Horus next plan would be a strike on the Manachean Commonwealth, a loyalist independent dominion within the Coronid Deeps to the galactic east of the Cyclops Cluster. This area was not left unguarded.^[1a] In the early stages of the Horus Heresy, the Commmonwealth would be one of the earliest prepared regions of Imperial space for the coming of war. Following news of the attrocity at Isstvan and word of Horus' betrayal reaching Terra itself, Port Maw was used as a layover and resupply station for the fleets which would be deployed to the ill-fated punitive mission to Isstvan V. When word of its disastrous outcome reached the leaders of the Coronid deeps, they at first scoffed and suppressed such reports. Only when the first battered ships of the loyalist survivors trickled in did the weight of what was to come dawn upon them. Messages calling for reinforcement and aid to Terra were lost to warp storms and static, and so the worlds of the Commonwealth could only prepare for the coming onslaught. The Commonwealth could call upon regiments kept to the standards of the Solar Auxilia pattern, thanks to its high technological and industrial basis allowing for such troops to be supplied and maintained^[1a], while the massive War Fleet of the Port Maw Armada would provide for its defense in the void.^[1c]

Prelude to Port Maw

Horus had not been unprepared. Traitor Agents were already embedded throughout the Coronid Deeps.^[1a] By the time of the Isstvan III atrocity, Horus had already used his influence as Warmaster to have elements of Port Maw's Armada scattered on deep patrols in space, chasing flimsy reports of pirates or xenos activity, or reinforcing distant warzones and conflicts even where they were not called for. By 006.M31, when the fires of rebellion were finally made clear, efforts by Port Maw to recall their fleet were greatly disrupted. The upsurge in warp turbulence so infamously associated with the Horus Heresy would make itself felt, and the fleets sent chasing after mist and shadows now found the threats very real and dire. Xenos raiders, piracy, attacks unknown warships and all manner of calamities assaulted their fleets. The Rogue Trader Rom Jhuttlander, who had served as pathfinder to Horus 63^rd expeditionary force, would launch raids from the Coronid Prohibited Zone, which Port Maw had been forbidden to enter by ancient decree. Soon the Warmaster's emissaries themselves would arrive, demanding dark compliance. Many deep range patrols simply did not return.^[1c]

Worse still, an unexpected appearance of the Ork Space Hulk Red Polyphemus in the region forced an entire battle group from Port Maw to be diverted to deal with the threat. Such a sudden attack by Orks that had seemingly been suppressed in the region for over 30 years would, in hind-sight, appear to be more than mere coincidence. Normally the fleet would call upon Legiones Astartes support to board and put an end to the space hulk, but deprived of this they were forced to commit to the dangerous task of bombarding and destroying the space hulk, all while Solar Auxilia forces kept greenskin counter attacks and invasions of nearby worlds by the Orks. Port Maw's battlegroup finally fragmented the Space Hulk in 007.M31, but taking a heavy toll in attrition throughout that time. By then, word had come that the Death Guard had arrived to mount an attack towards the Manachean Commonwealth itself, and forces from the surrounding region were called to muster at Port Maw.^[1c]

Treachery at Port Maw

The artificial planetoid of Port Maw was normally home to the War Fleet of Port Maw Armada, which included a score of battleships, dozens of squadrons of cruisers, countless hundreds of escort craft, and thousands of servitor-drone tenders, provision ships, troop transports and orbital lighters. These would soon be joined by reinforcing fleets from the rest of the Coronid Deeps, warships of the distant Agathean Domain, pirate-killers from the Cerada Nebula, and three huge War Arks from Forgeworld Cyclothrate. In addition to this, a great wave of refugee ships, mercantile ships fleeing systems under threat and ragged survivors of the battles in the Cyclops Cluster, and even a handful of survivors from the void battles at Istvaan V, though the Astartes vessels would not remain long. Many such ships were barely operational, while others had to be scuttled or set to drift lest their perilous state of disrepair pose a threat. Such numbers of vessels would be impossible for the normal human mind to bear, so coordination of the assembling armada was channeled through Port Maw's Mechanicum Astra Control Panopticon - a powerful broadcast tower ten kilometers high on Port Maw's southern pole. Cogitators would calculate ship movement data across the fleet and automate the control helms of the vast number of ships to prevent collisions. Though this automated control could always be overridden manually, anticipating a vulnerability, Port Maw's leaders had strengthened the encryption and defenses multiple times throughout the war. Deemed impregnable, the leaders of Port Maw could not anticipate the fatal flaw in the system which would be the betrayal of Archmagos-Astral Leit Mercuric, cyber-Ordinator of Port Maw, who had secretly sworn to Horus, as well as several of her acolytes and officers of the Imperialis Armada, all of whom were corrupted when they had served alongside the Word Bearers in the past.^[1c]

When the war finally arrived to Port Maw, the betrayal was put into motion. The Control Panopticon sent powerful signals and data-djinn to all the ships that had been so reliant upon. Vox-circuits burnt out, auguries were filled with static, auspex scanners shut down as systems failed as ships were suddenly blinded. Moving ships diverted or suddenly accelerated, crashing into each other, their wreckage flying into the paths of others. The crews of many, unbraced and unprepared for sudden impacts, were hurled against the walls of their vessels into a bloody pulp. Ship bridges were flooded with scrapcode. Over a hundred lesser vessels were overridden entirely, their ships venting their crew into the void, while the Machine Spirits of the larger vessels fought against the attack. At this same time, turncoat ships within the Port Maw fleet were left unaffected and began to fire upon their former allies, sowing terror and confusion, and causing many loyalist ships to surrender to traitor demands.^[1c]

The Provost-Marshals of Port Maw, having thwarted a mutiny in their own ranks, gathered elite armoured Veletari troops of the 905^th Lethe Cohort to storm the Control Panopticon, which failed to respond to communications and was now clearly the source of the malevolent signals. They fought their way past frenzied servitors, servo skulls, giant mechanical spiders, hulking traitor Tech Priests as heavily armoured as Terminators, and Castellan Class Automatons. Only a single Veletari soldier managed to survive, making his way to the control dais of the Panopticon and destroying it even as his helmet was being crushed by steel claws - ending the malignant signals.^[1c]

With the malignant signal from the Panopticon halted, order began to reassert itself as battle lines were now properly drawn between traitor and loyalist. Grand Admiral Ospheus LaBray thwarted a mutiny on Port Maw's flagship - the Triumph of Reason, a large command ship designed to direct an entire Segmentum fleet as needed. He ordered the Dictatus Class Ram-Battleship Kurga to destroy the now silent Panopticon tower. The Kurga smashed into the tower with its piercing ram claws fired melta-tipped harpoons spears into the tower, then burned its engines hard ripping the panopticon tower off its base and sending it adrift into the void.^[1c]

Meanwhile, far out into void, the rest of the reinforcement ships of assembling Port Maw Armada also had to deal with the Panopticon signal and mutiny among their own vessels, while others such as a squadron of cruisers from Agathon, stayed out of the fight, confused as to the battle that had no clear cause nor side to choose. At this time, one of the three Cyclothrate War-Arks, the Arithmetic of Violence, having thus far remained quietly out of the fight, unleashed a massive volley of void torpedos that devastated the Agatheans, now revealing the Cyclothratine Mechanicum fleet's true colours.^[1c]

Attack on Manachea

The Sons of Horus began their assault on Manachea. Striking at Hive Ilium on Manachea Vysidae, Horus' forces under Abaddon defeated the shocked but tenacious Imperial Army resistance. After capturing the Palace of Light, the Manachea Commonwealth folded to the traitors.^[1c][1d] It was then that Horus, the Death Guard, and the majority of the traitor forces left the region to conduct campaigns elsewhere, leaving a smaller garrison led by Taloc Thorne to oversee the Commonwealth's subordination. Meanwhile, the Iron Hands ship Red Talon of Clan Morragul under Autek Mor had arrived in the system, exacting vicious retribution on traitors and their collaborators wherever they could be found, striking at Gethsamaine Colonus in the Grail Abyss. In a murderous fury, Mor's troops used nuclear weapons to depopulate Gethsamaine.^[1d][2b]

While the ruling traitor Magos under Draykavac was still busy mopping up the last remnants of resistance in his newly-conquered sectors, a loyalist reinforcement fleet from the nearby Agathean Domain arrived under Lord Marshal Ireton MaSade. MaSade struck at the recently captured world of Numinal, creating a vicious conflict where his Solar Auxilia battled traitor Mechanicum forces. Knights, used by both sides, proved the decisive factor in the battle. The loyalists held firm and slowly began to overwhelm the traitor forces, and aided by local rebellions and small amounts of Imperial Fists and Raven Guard were able to win the day. Numinal had fallen to the loyalists.^[1d]

But despite the liberation of Numinal, much of the region still lay in traitor hands. Stalemate ensued, and the Manachean Commonwealth was devastated in a series of attacks and counterattacks.^[1d] At Lethe and Revorthe Keep, the loyalist Death Eagles Blackshields clashed with the Emperor's Children.^[1d]

The Siege of Epsilon-Stranivar IX

Epsilon-Stranivar IX, known during the Great Crusade of Fortress Stranivar, was a world found at the edge of the Coronid Deeps. By the time of the later stages of the Coronid Deeps campaign, the world had served as the last loyalist stronghold of Horus' flank, garrisoned by a force of small force of Imperial Fists, Raven Guard, Iron Hands, Salamanders, and Blood Angels. Refusing to yield, the traitors were faced with no other option but a major assault. But while the loyalists were united in a common cause, the traitors were divided among their own agendas.^[2a]

Thus a force of Iron Warriors of the 114th Grand Battalion, Alpha Legion companies, and a Death Guard host began their poorly coordinated push. Time and time again the Alpha Legion allowed the Iron Warriors to attack unsupported into guns and dug-in loyalist positions while using the confusion for their own pin-point raids. During the climatic battle of the campaign, the Siege of Vharna, the Traitor Host broke on the Loyalist lines. The 114th Grand Battalion was effectively abandoned by the Alpha Legion and Death Guard, left to act as a sacrificial rearguard. Of the 6,000 Iron Warriors who took to the field, less than a third would leave alive. The highest-ranked surviving Iron Warrior, Nârik Dreygur, swore that his fallen brothers would be avenged.^[2a]

However, the loyalist victory was short-lived as less than a year later the Sons of Horus launched a renewed attack that captured the planet.^[2a]

See also

• Battles of the Horus Heresy (List)
  • Mezoan Campaign

Sources

• 1: The Horus Heresy Book Four - Conquest:
  • 1a: pg. 18-19
  • 1b: pgs. 25-35
  • 1c: pgs. 36-52
  • 1d: pg. 158
  • 1e: pg. 159
• 2: The Horus Heresy Book Six - Retribution:
  • 2a: pg. 34
  • 2b: pg. 105