Scourging of Kerrack - 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.