The Scourging of Kerrack was an Imperial campaign conducted on the Agri-world of Kerrack in 932.M41 to rid it of the Chaos taint that had befallen it. What started as a mere workers' riot soon evolved into a planetary insurrection. Led by one of the dreaded Chaos Space Marines, Mahaur the Harvester, the Chaos Cultists of the Charnel Cult almost succeeded in vanquishing the Imperial defenders and seizing the weapons stockpile established by the Adeptus Administratum.
Fortunately for the Imperium, the arrival of unexpected reinforcements in the form of the 5th Company of the Star Phantoms Chapter of the Adeptus Astartes helped to turn the tide and secure victory for the servants of the Emperor. In recent years, the Scourging of Kerrack has increasingly become required reading for Imperial tacticians and military officers because of the paramount importance air power played in the successful outcome of the conflict.
The Roots of Heresy
- "The enemies of the Emperor will show us no mercy. We intend to extend to them the same courtesy!"
- — Group Captain Ardas Quinn, Kerrack Tactical Air Command
Kerrack is a peculiar world where life has always been harsh. The planet is dominated by a single large continent where the human population has naturally concentrated. This vast continent harbours Kerrack's single and most valuable resource: the great forests of mighty Cholam trees, some of them towering more than 200 Terran feet in height. Cholam roots only grow in humid environments, which means that beneath the canopy much of Kerrack's continent resembles a gigantic swamp. Although filtered through ancient technological artefacts that likely predate the birth of the Imperium, the water used to irrigate these forests is highly toxic. The Imperial presence on Kerrack is concentrated in a few factory-cities located on the shorelines. The harvested Cholam roots are processed there into a barely palatable but nutrient-rich grey gruel, before they are shipped to Kerrack's single spaceport at Ven Nys and then on to the overpopulated Hive Worlds across the Imperium and to support the Astra Militarum regiments engaged in the Karthago Crusade.
Since its establishment as an Imperial Agri-world, Kerrack's native population has deliberately been kept in a state of servitude and held to a lower technological standard than that of the wider Imperium. Organised in great family-groups, the men and women of the so-called Harvester Clans have toiled under the stern gaze of their Imperial overseers, hacking at the tough, fibrous roots of the Cholam trees. So thick were these forests that only travel on foot was possible, thus severely hindering quick transport of goods and personnel on Kerrack. Clansmen riots and insurrections were few and far between, though not unheard of. So in 926.M41, when the first clansmen rose against the Imperium, none could have foreseen the dramatic turn that events would take.
Upon learning of the first uprisings, Kerrack's Planetary Governor Vortgern Strick immediately ordered the Planetary Defence Forces to mobilise. His intent was to quickly smash the riots, but like a brush-fire, these revolts spread quickly, including amongst the PDF. All across the northern shore of the continent, from Algrist in the west to the Ven Nys spaceport in the east, all of the Imperial settlements came under attack, be it from the great mobs of Harvester Clans, now openly declaring themselves the "Charnel Cult" or insurrectionist elements of the Kerrack PDF. At the planetary capital of Calder's Ark, Governor Strick quickly found himself besieged in his own palace. Fortunately for the Governor, a sizable Astra Militarum garrison had been stationed at Calnix Island, to defend the Adeptus Administratum-controlled weapons and munition depot. There on "Fortress Calnix," Colonel Mortemar and his three thousand Cadian Shock Troops readied themselves for their decisive counterattack.
For the Imperial defenders, things looked grim. Colonel Mortemar knew that the enemy heavily outnumbered him. If he was caught in the open, his troops would be quickly annihilated. Secondly, the Cadians were only able to field about two hundred aircraft, not enough to deploy the Cadian forces as one, which would mean that his already meagre fighting force would need to be further divided to allow them to reach the designated battlefield. Furthermore, such large landings could only be conducted in the great factory-cities, most of which had already fallen to the enemy. A direct assault on Calder's Ark was deemed too risky, and so Colonel Mortemar settled for the capture of Algrist, the nearest settlement from which he could strike at the capital, break the siege of the Governor's palace and rally enough loyal troops to finally put down the rebellion.
In disciplined ranks and files, the brave Cadians boarded what Valkyries were available. A first group would storm the city, dig in and hold out against the enemy until a second wave of Loyalist troops could be ferried from Calnix Island. To improve the chances of the first assault wave, it would be supported by what aircraft the base could muster to serve as both air defence fighters and tactical air support. While Mortemar's strategy was sound, on the ground and in the air, things looked far more complicated.
First was the nature of the terrain. Like many provincial cities within the Imperium, Algrist was no grand planetary capital with wide avenues, grand plazas and elegant official buildings: it was an industrial town at the heart of a dense forest. Algrist's streets were narrow and its skyline dominated by the great bulk of the processing factories and worker habs which would take many hours of fierce street-to-street fighting to seize. The height of the Cholam trees -- some of which can grow to a height of more than 200 Imperial feet -- also meant that any approaching aircraft could not use the natural terrain to hide from the city's air defences, which would presumably be well manned by the Charnel Cult. Capturing Algrist would make for a dire prospect indeed.
To make things worse, as soon as the Imperial counterattack was launched, it ran into the enemy. Before even reaching their designated target, the Lightning Strike Fighters of Leonid Squadron who served as the spear-tip of the Imperial attack encountered unexpected enemies: defiled Thunderbolts of the Charnel Cult, formerly belonging to Kerrack's Planetary Defence Forces. Heavily loaded with bombs, as their prime target had been Algrist's anti-air guns, the normally nimble Lightnings made for easy targets. Intercepted while still over the Calnix Channel, a fierce dogfight erupted from which the Imperial fighters ultimately emerged victorious, but several of their numbers had been damaged or been forced to drop their payload into the sea and thus needed to return to base. The depleted first wave continued their attack, approaching Algrist from the sea. The Lightning pilots valiantly dropped to a dangerously low altitude, using the city's drainage trenches and channels as approach vectors to find their target. This allowed the Imperial pilots to close with their target while limiting their exposure to enemy fire, but also required the pilots to level out at the last possible moment, only narrowly avoiding crashing into the city's towering nutrient processing facilities. One pilot miscalculated his approach, pulled up too late and crashed at full speed into the city's ferrocrete flood walls. Forewarned of their approach, the Lightnings were welcomed by Autocannon and Manticore-platforms that spit fire from the ground.
Having been delayed by their unexpected skirmish above the Calnix Channel, the Imperial aircraft were still dealing with Algrist's air defences while the first wave of Mortemar's troop were inbound, further crowding the airspace. The Thunderbolts that made up the first wave's fighter escort soon gained altitude to engage their Renegade counterparts, while the infantry-laden Valkyries sped on. The heavier Vulture gunships outpaced the vulnerable transports, attacking the buildings surrounding the landing zones to keep the enemy occupied or being occasionally called in to destroy an enemy position previously missed by the Lightnings of Leonid Squadron. With typical diligence and the routine born of many battles, the Cadians rappelled down their transports' lines and immediately rushed into buildings, clearing out the enemy to secure a proper beachhead. Fierce firefights and heavy fighting erupted in the city's eastern quarters.
As soon as they had off-loaded their human cargo under the watchful eyes of their escorts, the Valkyries turned and raced back to Calnix Island where the second wave of Imperial troops waited to be ferried to the mainland. The Lightnings and Vultures remained on station, the Cadians ordering precision strikes wherever the enemy resistance was too tough to break, but their fuel was limited. The enemy would counterattack once the Imperial air support was forced to quit the battlefield, so the Cadians did not heedlessly rush in, but instead fortified their landing zones, waiting for the arrival of their reinforcements to properly take control of the city. As predicted, the Charnel Cult launched themselves at the Imperial attackers with great savagery, but the Cadians held their positions until the arrival of the refuelled Valkyries and Thunderbolts heralded the cultists' defeat. By the end of the day, Algrist was once again in Imperial hands.
The Fall of Calder's Ark
The reconquest of Algrist marked the first Imperial victory in the Scourging of Kerrack campaign. The Cadians had secured a valuable foothold on the mainland, yet unknown to Colonel Mortemar and his command staff, events were in motion that would strip this victory of its meaning. Unknown to the seasoned colonel, a voidship was approaching Kerrack, a vessel carrying none other than the Chaos Lord Mahaur the Harvester and his warband of Chaos Space Marines known as the Slaughterkin. Only a few solar hours after the fighting had ebbed in Algrist, Mahaur's vessel reached orbit and stationed itself above the planetary capital of Calder's Ark. Rather than bombard the capital from orbit, Mahaur unleashed the Slaughterkin's own aerial might, as scores of Hell Talons and Hell Blades descended like vultures upon a carcass. Heedless of the losses they might inflict on their allies in the Charnel Cult, the Slaugherkin ravaged Calder's Ark, carpet-bombing all its districts save for the Governor's Palace -- for Mahaur intended to seize it to use as his own base of operations. The Slaughterkin rejoiced in the carnage they wrought as entire units of Loyalist PDF were annihilated from the air. The survivors of these bombardments were often in such poor shape that they preferred to go into hiding or to desert rather than face their true enemy.
When all but the Governor's Palace lay in ruins, the Slaughterkin landed their own troops on Kerrack, their Chaos Space Marine general at their head. Such was the frenzy Mahaur instilled in his troops that in less than a solar hour of fighting the Slaughterkin took the Governor's Palace, slaughtering what remained of the governor's loyal bodyguard before leading their lord to the palace's throne room, where the Chaos Cultists had cornered the rightful ruler of Kerrack, Imperial Governor Vortigern Strick. To his credit, the captured Imperial Governor did not cower or plead for his life as Mahaur the Harvester strangled him with his elaborate gold chain of office. Vortigern Strick's death marked the end of Imperial resistance within the planetary capital and its surroundings. Henceforth the Cadians would need to fight without the assistance of Kerrack's militia.
While the Harvester now ruled in Calder's Ark, the Charnel Cult gradually took control of Kerrack's other cities, the Imperial defenders disheartened by the quick fall of the capital and their commander's subsequent death. Under Mahaur's direction, the arcane technologies regulating and purging the waters of Kerrack's swamps and seas were tampered with. The great filtration towers began to increase the water's toxicity levels rather than diminishing it. This perversion poisoned the surrounding land as huge regions of forest began to wither and die. Even the sturdy Cholam trees were overcome by the toxic sludge that bathed their roots, heralding the food shortages to come for many other nearby worlds of the Imperium and regiments of the Astra Militarum engaged in the Karthago Crusade should Kerrack fall. Knowing he had only a short respite, Colonel Mortemar carefully reconsidered his position. While Algrist had been captured, the death of Vortigern Strick and the remaining Loyalist PDF meant that his prime objective had been denied. The enemy had been reinforced and by taking Algrist, the remaining Imperials were much closer to the enemy's main force than before. Only the township of Rorth stood between Mortemar and the Harvester, and that town would also soon fall.
In truth, only two options remained: reinforce Algrist and try to hold out against the crushing numbers of the Charnel Cults and the Slaughterkin, or fall back to Calnix Island where the terrain heavily favoured the defenders. With a heavy heart, Colonel Mortemar ordered his troops to evacuate Algrist. The unending air-ballet began anew as disciplined files of Cadian Shock Troops boarded their Valkyries to abandon the city they had fought so hard to conquer. The Cadians' continued lack of transport would hinder them greatly: the enemy was already on its way, force-marching through the swamps and forests, closing on Algrist. The evacuation had barely begun when the first enemy units were spotted by the perimeter guards.
Using their own flyers to converge quickly on Algrist, the Slaughterkin led a sizeable contingent of Renegade PDF to attack the retreating Imperial Guardsmen. With the same savagery as at Calder's Ark, the Slaughterkin broke through the exterior positions, but the discipline and tenacity of the Cadians slowed their progress towards the heart of the city. Colonel Mortemar soon realized that he would not be able to secure safe transport for all his troops; even now, Thunderbolts were struggling to keep the Valkyries safe from squadrons of marauding Hell Blades. Reluctantly, Colonel Mortemar designated those companies and platoons that would act as a rear-guard for their comrades before boarding a transport himself. He had effectively condemned hundreds of his men to die, but such were the hard realities of war. Despite knowing they were doomed, the Cadian rearguard acquitted themselves well, buying enough time so that all the Imperial transports -- some overladen with troops and wounded -- could take off. For an entire afternoon, the Imperial rearguard slowed the hordes of the Slaughterkin and the Charnel Cult that had begun to swarm the city. The situation changed around nightfall, as the defenders were quickly overwhelmed. Those lucky enough to die in the fighting were spared the bloody rituals and sacrifices to the Blood God the Charnel Cults conducted around the great bonfires they had lit.
Attack on Fortress Calnix
Colonel Mortemar's decision to fall back from Algrist was a sound one, for Calnix Island -- or "Fortress Calnix" as it was known by the locals -- offered many advantages. First, since it was an island, the enemy would have to conduct either an airborne or an amphibious assault, both requiring a great deal of planning and logistical support. Furthermore, for generations Calnix Island had been the main military base of the Imperium on Kerrack, which meant that it had been well fortified. These fortifications included hard-built artillery redoubts with pre-sighted guns in perfect working condition that carried such impressive names as "The Grey Wall", "Abis Sheddin" and "Sobal Beach". Rigorous fire drills had transformed the eastern part of the island into a landscape of craters and loose rubble, one that would heavily favour the defenders. Calnix Island also harboured the principal airfields of the Kerrack Air Command and the twenty full-strength squadrons under its orders. These squadrons ranged from light Lightnings to the far heavier Marauder Destroyers and would enable Mortemar to coordinate both air support and air cover. Lastly, the island also harboured Administratum-led munition plants and weapons reserves, the proverbial armoury which would ensure that the Cadians would go down guns blazing. These impressive defences would have deterred most conventional attackers, but the deluded and fanatical worshippers of Chaos sought to capitalise on their advantage and almost immediately attacked the last Imperial stronghold on Kerrack.
For the massed ranks of the Charnel Cult, the frothing and steaming chem-seas around Calnix Island formed an impenetrable barrier, and so the first attackers of Forteress Calnix came from the Harvester's own warband, the Slaughterkin. Powered by their screaming, daemonically-infused engines, the bat-like silhouettes of Hell Talons -- fighter craft forged by the Dark Mechanicus within the Maelstrom -- flew over the Calnix Channel, intent on wreaking havoc on the last Imperials on Kerrack. They were resolutely met by the Thunderbolts and Lightnings of the Kerrack Air Command. These first overzealous incursions were rapidly shot down, but the situation in the air soon changed. Loathe to waste their own strength, the Slaughterkin gathered what Renegade fighters they could and threw them into the fight. Thanks to these Renegade pilots and their Imperial-issued materiel, the attackers had the advantage of numbers and hoped to wear down the Imperial squadrons. Soon, the unmistakable drone of Thunderbolt flights launching could be heard from both ends of the Calnix Channel, the Imperial aircraft rushing to meet the defiled fighters whose Imperial sigils and defence force markings had crudely been defiled or obscured by blood-painted sigils in the dark language of Chaos. As corrupted Imperial fighter-pilots fought those they had called brothers mere solar days before, the Slaughterkin's Hell Talons and Hell Blades held back, revelling at the fratricidal carnage that unfolded beneath them before picking off the wounded, for the Blood God cared little whose blood flowed as long as the bloodshed continued.
On the ground, Colonel Mortemar knew that the raging air battle offered only a short respite before the inevitable ground assault by the Harvester's forces. The Imperial defenders had expanded and strengthened the already impressive fortification network on Calnix Island. This did not escape the watchful eyes of the Slaughterkin-pilots, who sought to disturb the Cadians' efforts. Brightly-coloured Slaughterkin Hell Talons launched several bombing runs, targeting bunkers, gun emplacements and newly-dug trenches. Fortunately for the defenders, the Slaughterkin's bloodlust was up and when presented with a far more tempting target than mere earthworks, they could seldom resist. Kerrack Air Command soon learned how to use isolated Lightning fighters as bait, the Hell Talons breaking off their bombing run to engage the Loyalist fighter, screaming incoherent insults and challenges over open Vox channels while racing toward their new target. Using his fighter's greater speed, the Lightning pilot would then lead his pursuer right into the concentrated fire of a Hydra Flak Tank or into the path of hidden Imperial fighters attacking from above. If these attacks failed to disrupt the Cadians' effort, they nevertheless succeeded in inflicting some damage, especially at Sobal Beach, the portion of the Imperial defence line facing Ven Nys Spaceport.
Day after day, fierce aerial battles and air raids raged above the Calnix Channel, Mahaur the Harvester intending to wear the defenders down and then break their defences open. Only the continued efforts and the often valiant sacrifices of the pilots of Kerrack Air Command kept the attackers at bay. Growing increasingly frustrated, Mahaur changed tactics. In order to reduce the island's fortifications to rubble, Mahaur ordered the vast majority of the Chaos bombers under his command to conduct a single, focused attack on the western end of the defences at Sobal Beach. From Rorth and Calder's Ark, Ven Deth and Ven Nys Spaceport, the mighty Khornate air armada took flight.
The first Imperial formation to encounter this massive air raid was a routine air patrol that mostly consisted of the lighter Lightning fighters. Fortunately for the defenders, the patrol also encompassed the Imperial ace Ulrik Bex and his personal wing of Avenger fighter-bombers. Bex warned Kerrack Air Command of their impending doom before ordering his patrol to attack. If the defences of Sotha Beach were to hold, they would need time to prepare, and Kerrack Air Command also needed time to mobilise what operational aircraft remained and coordinate a counterattack. Regardless of the chances of survival, Ulrik Bek ordered the pilots under his command to form up on him and attack the enemy. His plan was to lure the most aggressive Slaughterkin pilots into a pursuit, thus depriving the Chaos bombing waves of their fighter escorts. Luckily for Bex, his fighters had the advantage of altitude and the sun at their back -- a textbook advantage for an attack position.
Summoning their courage, the Imperial pilots picked their targets and plunged into the massed ranks of Chaos bombers. With the sun blinding them, the Slaughterkin only located the attackers when they opened fire. Hitting a few targets on their first pass, the Imperial pilots narrowly avoided collision, traversing the enemy's tightly-packed formation before seeking shelter within the clouds. As intended, the Slaughterkin's fighters gave chase, led by a triumvirate of jet-black Hell Blades. Ulrik Bex ordered his wingmen to break from the fighting while he turned his Avenger and charged the enemy anew, determined to buy his friends more time to make good their escape. Eyewitness accounts of the few survivors from Bex's squadron reported that Bex's Avenger was literally torn apart by the three black Hell Blades which evaded every attempt by Bex to bring them down.
But Bex's sacrifice was not in vain, as on Sobal Beach the disciplined Cadians now manned their defences, every anti-air or pintle-mounted weapon tracking the sky and ready to unleash hell at the closing aircraft. As the first Hell Talons came into sight, Group Captain Quinn's hastily assembled squadrons of Imperial fighters raced over the Cadians' head. Quinn was determined to stop the enemy from reaching Calnix's shores. Both waves of aircraft clashed a few kilometres out at sea, the defenders of Sotha Beach mesmerised by the ferocious dogfight they were witnessing. Soon the battle degenerated into a swirling maelstrom where every pilot had to look after himself. The Imperial Thunderbolt pilots put their machines' legendary resilience to the test, diving right into the heart of enemy formations, guns ablaze, intent on causing as much damage as they could while simultaneously drawing the attention of the enemy fighter escort so that the light and more fragile Lightnings could close in with their targets.
As the battle reached its shores, Sotha Beach's air-defences kicked in, their gun-batteries firing into the melee, careful not to hit any Imperial fighters. Soon after, the first Hell Talons reached their targets and began dropping their payloads on the beach and its fortifications. The explosions created huge geysers of earth, drawing the defenders' attention away from the raging inferno above their heads, just in time to see the first grotesque Daemon Engines thrashing through the acidic surf of Kerrack's chem-seas and setting foot on the ground. Behind them, row upon row of landing barges transported the ragged hordes of the Charnel Cult. Mahaur the Harvester had used the air assault to hide his main invasion force in plain sight. With the certainty that this was Mahaur's endgame, the defenders of Sobal Beach shifted their focus to these new targets and opened fire.
While Mahaur himself was one of the terrifying Chaos Space Marines and his warband counted quite a few of those ultimate warriors of evil among their number, the massed ranks of the Harvester's armies now closing on Sotha Beach were mere mortals: deluded Kerrackii-natives that had joined the Charnel Cult, Renegade members of the Planetary Defence Forces and those murderers and psychopaths who served as the Slaughterkin's rank-and-file. The defences of Sotha Beach -- improved over generations -- had been specially designed to repel such an assault. Being well-versed in fighting the horrors of the Warp, the Cadians concentrated their heaviest weapons on the Daemon Engines, confident that their discipline and military training would bring them victory over other unaugmented humans. The garrison's efforts halted the enemy advance, pinning them on the beach itself where the Cadians' heavy guns could slowly destroy them. But the ground war soon reached a stalemate, with Mahaur's army unable to break through the Imperial defence line while at the same time stubbornly refusing to retreat. The fate of this battle would ultimately be determined in the skies.
As casualties on both sides steadily rose and the fate of the entire battle hung in balance, the Imperium landed a decisive blow. Focussing on the most dangerous elements amongst the Slaugherkin's air armada, Commander Karl Neider of the Imperial Navy launched a furious assault on one of the daemonically-infused black Hell Blades. Locking onto his target, Neider unleashed his final missiles. The profane craft exploded and tumbled to the ground, leaving a trail of fire and smoke. The impromptu death of one of their tribunes unexpectedly caused the Slaughterkin to scatter. The remaining Hell Talons immediately broke off their attack, abandoning their allies both in the air and on the ground. A small number of Slaughterkin pilots entered a berserker fury and launched themselves in wild abandon at the Imperial forces, fighting until their weapons ran out of ammunition or their fighters plummeted from the sky because of empty fuel tanks.
Despite their victory, the butcher's bill had been tremendously high, both on the ground and in the air. Sotha Beach had held, but barely. The vast majority of its fortifications now lay in ruins and the Cadian Shock Troops' death toll was similarly high. The Imperial Navy and Kerrack PDF squadrons had fared little better, for whereas most of the downed fighters could be repaired or stripped for parts, few of the pilots forced to eject had been saved. Many of the defenders shuddered at the gruesome fate that awaited those unlucky few when they were seized by the insane followers of the Charnel Cult. While the enemy had not claimed Calnix Island, every man and woman knew in his heart that they were now trapped on the island. The bloody mathematics of war all indicated the same conclusion -- another such "victory" would be their death. A cold realisation settled in, choking every glimmer of hope or joy, for the defenders had merely postponed the inevitable.
Aid Unlooked For
It was then -- in their darkest hour -- that chance finally smiled upon Kerrack's defenders. Long-dead orbital Vox channels suddenly came to life with the scrambled transmissions from an unidentified Imperial spacecraft heading to the beleaguered planet. Mahaur's small fleet had long since destroyed or chased off all Imperial vessels in the system, meaning this unidentified visitor came from beyond Kerrack's bounds. The faint embers of hope burned high as the news became known amongst the defenders. Most assumed that their prayers had been heard and that the newcomer would bring much-needed reinforcements. However, the Cadians' commander, Colonel Mortmar, had no means to contact this new vessel, as the Vox transmitters of the Calnix Garrison were not powerful enough for their signal to break orbit. Whoever the occupants of this new voidship were, they had no idea what was happening on Kerrack.
Colonel Mortemar reevaluated his situation. Remaining on Calnix Island and focussing on rebuilding the defences of Sotha Beach seemed pointless, for Marhaur's troops still greatly outnumbered them, both on the ground and in the air. The enemy was currently in a state of disarray, which meant that if the defenders of Calnix Island intended to land one last blow, it would have to be now. If the voidship approaching Kerrack did carry possible reinforcements, then Mortemar and the defenders would need to make contact with them in order to coordinate their efforts, be it to mount an offensive against the Harvester or ultimately organise a retreat from Calnix Island. Kerrack sported only two relays powerful enough to guarantee interstellar communication -- the Governor's Palace at Calder's Ark and the Central Communication Tower at Ven Nys Spaceport. Of course, both installations were currently in enemy hands, but the defenders' best chance at survival would be to contact the unidentified spacecraft. An assault on Calder's Ark was immediately dismissed, as it was akin to suicide. Mahaur the Harvester himself currently resided in the Governor's Palace, and it was where the Slaughterkin had retreated to. The only viable option was Ven Nys. Reconnaissance flights indicated that the spaceport was mostly held by the Charnel Cult and that their numbers were far more limited than in other locations, for the enemy believed the defenders broken and trapped on Calnix Island. The Harvester believed the spaceport secured. It was time to show him the error of that assumption. Invigorated by this news, Colonel Mortemar began to muster every available man, woman and aircraft for one last strike.
With the armies of the Harvester still regrouping and under cover of night, the assaulting Imperial forces had no difficulty in breaking through the scattering armies to set course for Ven Nys Spaceport. As for the assault on Algrist, the first wave of Imperial flyers was composed of Lightnings, Thunderbolts and the few Avengers available to Kerrack Air Command. Their mission was to neutralise the enemy air defences so that the Valkyries would be able to land safely. As these flyers closed in on their targets, they realised that Mortemar's intelligence on the Ven Nys garrison was flawed: the spaceport's Hydra and Manticore batteries were fully operational and crewed not by Charnel Cultists, but Renegade PDF. As a grey dawn heralded the rise of Kerrack's single sun, the sky was soon filled with tracer fire.
Mortemar's first attack wave did not succeed in entirely knocking out the spaceport's air defences before they were called to intercept hastily scrambled Slaughterkin fighters. By the time the Valkyries made their approach, Lightnings, Thunderbolts, Hell Blades and Hell Talons had already started their deadly ballet in the sky. Unsupported, the lead Valkyrie's pilot chose to dive low, threading the needle and taking his transport right through the streets of the huge hangar complex that constituted the suburbs of the spaceport, dodging fire from the ground. Not every Imperial transport made it. Several were shot down or crashed into a building, but most were able to reach the heart of the spaceport facilities, disgorging their troops right at the foot of the central command complex. The Cadians quickly assembled into platoons and rushed the Chaotic defenders, taking control of the Central Communication Tower as well as the attending buildings and their gun platforms. The engineers who accompanied the attack force quickly set to work, making sure Colonel Mortemar's call for aid would be transmitted. As the last words were broadcast, the tower's Augurs detected a new wave of incoming enemy aircraft, the massive and unmistakable silhouette of a super-heavy Harbinger bomber at their fore.
The lumbering behemoth that was the Harbinger closed in on Colonel Mortemar's position, impervious to the missile and cannon fire the Loyalists threw at it. The Harbinger's own twin-linked Autocannon-turrets opened up in retaliation, while its fighter escort joined the fray, shooting down many of the Imperial flyers trying to reach it. The bomber was finally brought down by the valiant efforts of Commander Neider. With both fuel and ammunition exhausted, Commander Neider resolved to make the ultimate sacrifice. Using his Lightning fighter as an improvised missile, he crashed his aircraft into the Harbinger's engines. Unable to maintain its altitude, the bomber went down, but the Harbinger's explosive payload still inflicted great casualties on the Imperial troops. Several outlying positions were annihilated even though the Harbinger had crashed a few blocks from the Central Communication Tower. Running dangerously low on fuel, the remaining Imperial fighters abandoned the sky to their enemy, Colonel Mortemar's troops scrambling to find cover before the Hell Talons and Hell Blades began their strafing runs anew.
Effectively pinned down by the enemy's air superiority, the Imperial Guardsmen were powerless to prevent Mahaur's ground forces from encircling them. The assault of the cultists had left the Guard's position in tatters. Only isolated pockets of Imperial troops still held out, as their occupants desperately fought for survival. By midday, the refuelled and rearmed Imperial air assets joined the fray, heralding the arrival of a second wave of Imperial transports carrying much-needed reinforcements. The Lightnings and Thunderbolts tore into their enemy counterparts and momentarily tipped the battle in the Imperium's favour. Yet the greater numbers of the Renegade PDF and Slaughterkin flyers soon forced them to retreat once more. Knowing full well that they could not land in the contested spaceports, the Imperial reinforcements deployed by using Grav-Chutes. But calamity struck again when many of the reinforcing squads were shot down while still in the air. Only a fraction of the reinforcements successfully reached Imperial positions unharmed. With the Charnel Cultists closing in from all sides and ammunition beginning to run low, most Cadians mumbled prayers to the God-Emperor.
Unknown to the increasingly desperate Guardsmen, their prayers would soon be answered. The unidentified spacecraft that had entered the system was indeed an Imperial vessel: the Fires of Salvation, an Adeptus Astartes Strike Cruiser belonging to the Star Phantoms Chapter. The Fires of Salvation carried the full might of the Star Phantoms' 5th Battle Company, which had been previously engaged in the Karthago Crusade to liberate the Karthago Sector from the Orks that had invaded it. The Star Phantoms had come to Kerrack with the intent of resupplying at the great Administratum stockpiles on Calnix Island, but not having received any response to his repeated hails, the company's commander, Captain Calphax, had ordered his Strike Cruiser to approach the planet covertly, not knowing that Kerrack was under invasion by the Forces of Chaos.
Shortly after entering the inner system, the Fires of Salvation detected Mahaur's fleet in orbit above the Agri-World. The two main ships in the Slaughterkin's fleet -- the Devastation-class Cruiser Crimson Reliquary and a captured Dauntless-class Light Cruiser identifying itself as the Harrower -- outgunned the Fires of Salvation, yet the Strike Cruiser did not retreat. At last receiving Mortemar's transmission, Captain Calphax's decision was set: the Star Phantom would take the fight to the Slaughterkin and rescue the colonel and his troops. Engaging its powerful thrusters at maximum, the Fires of Salvation closed with the planet, conducting a single pass above it in order to launch its own complement of troops before breaking orbit. Rather than trying to flee, the Strike Cruiser charged the enemy fleet head on, its Void Shields fully operational and its guns loaded and ready to fire. The Harrower tried to intercept the onrushing Fires of Salvation, but failed to stop it, the Strike Cruiser's gunnery masters stripping the smaller craft of its Void Shields before sending high-explosive shells into the Light Cruiser's stern and engine decks, effectively crippling it. Yet the Harrower 's broadside had caused some damage, as testified by the shimmering trail of debris the Strike Cruiser left in its wake. Its mission fulfilled, the Fires of Salvation headed to the safety of the inner asteroid belt, drawing off the Crimson Reliquary. The Emperor's Angels of Death had been unleashed on Kerrack.
The first sign the besieged Cadians had of their arrival was the unexpected destruction of several of the Hell Blades. Using their superior firepower to clear a path through the Chaos aircraft, the Thunderhawk gunships of the Fires of Salvation made for the ground. As soon as they had touched down, the front ramps lowered and disciplined squads of white-armoured Space Marines left their transports before the Thunderhawks took off again. Alongside these eighty Space Marines, Thunderhawk Transporters ferried rugged-looking tanks which soon joined their brothers on foot in the counterattack. Both tanks and armoured giants wore the distinctive symbol common to the Star Phantoms: the skull-bedecked hourglass -- two powerful symbols of death, for in the wake of the Star Phantoms death walked the streets of Ven Nys Spaceport. The Charnel Cultists proved unable to match the fury of the Emperor's finest soldiers. A single venerable Storm Eagle pierced the sky and delivered Captain Calphax and his personal retinue to the battlefield. The fury of the Star Phantoms was terrible to behold and soon the armies of the Harvester preferred to flee before the Space Marines' onslaught, leaving the ravaged spaceport in the hands of the Imperium.
The Harvester's Doom
As the fighting ebbed at Ven Nys, Colonel Mortemar and his survivors were finally able to meet with their saviours. Captain Calphax personally came before the battered men and women of the Cadian regiments and thanked them for their continued efforts in safeguarding the Emperor's domains. Although the Star Phantoms' 5th Company was bound by duty and honour to return quickly to the Karthago Crusade, the Star Phantoms would not permit Chaos to emerge victorious from this war and claim Kerrack as their own. Kerrack would be denied to the forces of Chaos, no matter how high the cost to the Astartes. Even after the severe losses inflicted upon the enemy at the spaceport, the Charnel Cultists still greatly outnumbered the Imperial defenders. Despite the presence of this new Imperial force on Kerrack, the tactical situation remained unchanged: Mahaur's army still occupied all of Kerrack's major cities and even the Loyalists' control of the spaceport would have to be surrendered in the face of a counterattack. Lacking both the time and the numbers to take back each city, the Star Phantoms decided to concentrate their efforts on eliminating Mahaur and his warband, the Slaughterkin. Following this decapitation strike, the leaderless hordes of the Charnel Cult could be fought by later reinforcements or those troops already present on Kerrack.
Although an assault on the capital of Calder's Ark offered them their best chance at a swift and decisive victory, the Imperial commanders were well aware that this plan also presented considerable risks. The former planetary capital had likely been heavily fortified, if not by the ill-disciplined cultists, then at least by the more experienced warriors of the Slaughterkin. As with most Chaos uprisings, the mortal servants of the Dark Gods tended to deify and venerate their so-called liberators, and so it was safe to assume that a large congregation of Charnel Cultists would also be encamped at Calder's Ark. If their attack failed to meet its objectives, the Imperial soldiers and Space Marines would quickly be overwhelmed and none would remain to oppose the Harvester. Captain Calphax assured Colonel Mortemar and his command staff that the Fires of Salvation had been specifically tasked with harassing the enemy in orbit to prevent an assault by the Chaos fleet. While the Star Phantoms gathered in prayer, ammunition and spare parts were ferried from the great depots on Calnix Island to Ven Nys. The Star Phantoms' assault on Calder's Ark would be supported by every last Imperial fighter, bomber, transport and soldier still in decent condition to fight. Having reconsecrated their weapons and their souls to the service of the Master of Mankind, the Star Phantoms boarded their Thunderhawks and quickly departed.
As the pearl-white Astartes gunships approached their target, none of their passengers would have recognised Calder's Ark as the proud Imperial bastion it had once been. Except for the Governor's Palace, where the mangled corpse of its loyal defenders had been strung up like ornate gargoyles, the city was in ruins. Blood-soaked hordes of screaming Charnel Cultists now prowled its streets like predators on the hunt while above the city the sky was filled with the cruel shapes of Hell Blades and Hell Talons, circling above it like a flock of carrion-birds hungrily eyeing a fresh carcass. These Slaughterkin fighters were the first to see their enemy's arrival and immediately converged on them. Beset from both ground and air, even the Thunderhawks' thick armour plating would not hold out for long. Fortunately, the Star Phantoms were not alone. The remaining Imperial air squadrons turned the tide, their timely arrival scattering the Renegade aircraft and allowing the Thunderhawks to touch down and deploy the 5th Company. The Star Phantoms had landed amongst the rubble that were once the central districts of Calder's Ark. With their armoured vehicles to the fore, the Star Phantoms quickly began to move in the direction of Mahaur's stronghold, the roaming bands of Charnel Cultists they encountered barely breaking their stride. The final battle for Kerrack had begun.
Meanwhile, the brawl in the air over Calder's Ark was reaching its climax. In the confused melee of darting aircraft, only the lightning-fast reflexes of the most experienced human pilots would see them through this fight. None dared confront the Thunderhawks and their mighty firepower, but the sizeable gunships were slow to turn and the enemy capitalised on the greater manoeuvrability of their fighters. It was in this nightmarish scene that the last wave of Imperial aircraft arrived: the Valkyries carrying Colonel Mortemar and his Cadian Shock Troopers. Long inured to the dangers of flying into the teeth of hell, the Valkyrie pilots fearlessly dived, delivering the Imperial Guardsmen directly into the developing firefight. Soon, the battle raged all over the former capital, the Star Phantoms unleashing the terrifying firepower their Chapter was famed for, only the two force commanders had yet to show themselves. While his battle-brothers persecuted the war on the ground, Captain Calphax and a hand-chosen squad were still in their Storm Eagle, waiting for the Harvester to show his ugly head. Despite the fierceness of the fighting, the enemy commander had yet to be seen. Knowing that the advantage of surprise was soon to be lost, Captain Calphax sought out Mahaur to slay him personally. The Storm Eagle's powerful Vengeance Launcher blasted a path through the palace's defences. Finally unleashed, Captain Calphax vented his fury on those Slaughterkin that tried to bar their way. From the highest tower of the Imperial complex, the Harvester observed his men being slaughtered, his ornate armour easily standing out.
When Calphax finally reached the top of the tower, the Master of the Slaughterkin, the polished bones of his victims bedecking his Power Armour was ready, his Power Sword drawn. As the Star Phantom and the Harvester clashed in a blur of powered blades and plasma bolts, the darting aircraft above mirrored the fight below. The Hell Blades sought to pierce Thunderhawk armour while Avengers shot down dozens of Hell Blades with a stream of shells delivered by their Avenger Bolt Cannons. Finally, Mahaur fell, caught in a crossfire unleashed by the Star Phantoms around Captain Calphax, yet he did not die. As he fell, Mahaur's grievious wound began to bubble and expand. Soon the Harvester was convulsing, grasping at his mutating flesh as his body mass began to swell. New eyes and fang-rimmed mouths opened up, leaving the once-mighty Chaos Lord a mewling, slithering mass of mutating flesh. Mahaur the Harvester's failure had angered his dark masters and they had transformed him into a Chaos Spawn as a visible sign of their discontent. Although Mahaur no longer posed a threat, the fighting did not ebb. Seeing their master brought low, the remaining Slaughterkin launched themselves at the Star Phantoms, seeking vengeance upon them. In a disciplined fashion, the Star Phantoms retreated back to their Storm Eagle, paving their way with enemy dead. As soon as Captain Calphax stepped onboard, he gave the order for all Imperial fighters to unleash everything they had on the Governor's Palace.
As the Storm Eagle soared away, the former seat of Imperial power was engulfed in a thundering conflagration, as bombs fell on the complex while the Thunderhawks brought down Palace's curtain wall with their Thunderhawk Cannons and Turbo-Laser Destructors. Banks of missiles were fired at the benighted structure, bathing it in flames until it collapsed upon the remaining Saughterkin, consuming them in the raging inferno. The profane thing the Harvester had become died with them, screaming its agony from a dozen throats. Seeing the destruction of their allies and their lord's stronghold, the remaining Cultists were filled with fear, and the Charnel Cult soon fled the battlefield, seeking shelter in the near-endless forests of Kerrack. The battle for Calder's Ark and the whole of Kerrack had been won.
Kerrack had been saved from certain perdition, although thousands of cultists were still present in the dense Cholam-forest. The Star Phantoms could not stay to completely purge the taint of Chaos for Kerrack, although while they liberated Kerrack's remaining cities. The war on Kerrack was proclaimed a great victory for the Imperium, though the death toll numbered in the tens of thousands. As many of its precious forests had been poisoned, Kerrack's agricultural output dropped drastically, which caused famines on an unprecedented scale on those worlds depending on Kerrack's exports to survive and represented a grave logistical challenge to the Imperial forces engaged in the Karthago Crusade. Though millions had died, the Imperium considered these lives a small price to pay to prevent Chaos from claiming one of Mankind's worlds.
Astra Militarum reinforcements were sent to Kerrack to relieve Colonel Mortemar's depleted regiments and hunt down the surviving cultists. For many standard years after the end of the war, the hunt for the surviving cultists continued, and the great forests were purged with lasfire and flames. Although most were believed to have been culled, rumours persisted for many solar decades that the descendants of the Charnel Cult were conducting heathen rituals in the darkest shadows of the Cholam trees.
- Imperial Armour Aeronautica, pp. 76-84
- Imperial Armour Volume Thirteen - War Machines of the Lost and the Damned, pg. 25