Before long, the Drukhari fleet, piloted by the psykers of the Legion of the Damned, plummeted toward the starports adjacent to the primary Hive Spire of Planet Bard. The Astra Militarum defenders let out a collective roar of defiance the moment they saw these treacherous xenos vessels breach the clouds.
The Unforgiven ignited their jump packs, soaring into defensive positions. They watched the alien warships with grim vigilance, ready to exterminate the xenos and earn the notice of their Gene-father.
Yet, as the heavy boarding ramps slammed down, it was not xenos that spilled forth, but countless humans.
Despite the shock, the Dark Angels did not lower their guard. They commanded the Astra Militarum to level their heavy weaponry, holding the masses at gunpoint.
A towering figure then emerged, a knight of such imposing majesty that the Dark Angels instinctively parted, bowing their heads in reverence. It was the First Primarch, Lion El'Jonson.
The Lion had come here drawn by a distant yet hauntingly familiar psychic resonance. It was the soul-trace of one of his long-lost brothers.
Finally, the Lion saw them: ghostly Astartes wreathed in roaring, ethereal flames emerging from the ships. Their heraldry and markings were unknown to any living record; only a few grizzled veterans whispered in awe: "The Emperor's messengers... the Legion of the Damned."
As the Lion approached, the spectral Astartes moved aside in eerie silence, watching the First Primarch pass until he stood before a figure of immense stature whose head was a raging inferno of white-hot fire.
"Ferrus..." the Lion murmured. Though he could not see a face, the frame and the contours of the power armor were unmistakable.
The burning Primarch said nothing. He merely pointed a finger toward the earth ahead.
No words were needed. The Lion understood his brother's silent warning instantly. He raised the Lion Sword and let out a thunderous command that echoed across the plaza: "Prepare for battle!"
Simultaneous with the Lion's order came the sound of a world-shaking detonation.
Like a storm of emerald fire, green drop pods began to pierce the thick, yellowish-grey smog of Bard's polluted atmosphere, slamming into the surface with violent force. The Orks gathered outside and the surrounding scrap-factories were pulverized beneath the weight of the arrival.
First came the smaller pods, followed by increasingly massive hulls. Finally, six metal monstrosities of Titan-scale descended. These Parasite Engines looked like nightmare hybrids of mosquitoes and rats forged from cold iron, crawling forward on six long, spindly mechanical legs.
From atop these walking city-Titans, countless Warp-weapons opened fire, vaporizing the Orks in a green mist of gore.
Then, from the Parasite Engines, the drop pods, and every shadow in between, a tide of Skaven erupted.
The ratmen immediately clashed with the Orks. The Greenskins, usually masters of attrition, were utterly overwhelmed by the sheer, chittering numbers. Ultra Stormvermin and Rat Ogres tore through the Orks and Squigs with flaying claws and Warp-drills.
Already exhausted from their war with the humans and seeing their orbital fleet shattered by the Clan Skryre main fleet, the Orks stood no chance. They broke and fled toward the mountains and out-zones in a disorganized rout.
With the Orks cleared, the Skaven turned their malevolent, beady eyes toward the sky-piercing walls of the human Hive.
"Ready! Check your magazines!"
Astra Militarum officers screamed orders, while Commissars raised power swords, shouting litanies to bolster morale. The knowledge that a legendary Primarch and the Emperor's Angels stood behind them filled the mortal soldiers with a frantic, desperate courage.
Thousands of Basilisks, Chimeras, and heavy weapon batteries were rapidly deployed. Though the Lion lacked Guilliman's genius for logistics, he was a master of strategy; he immediately organized the defense based on the Skaven's previous behavioral patterns during the assault on The Rock.
The mortals formed layers of barriers at the front, while the Dark Angels took up positions in the shadowed corners and narrow ducts where the mortals could not be trusted to hold.
Clan Skryre began its move. Countless warp-tech monstrosities were hauled onto the field. The Lion observed these war engines; they were crude, rivaling the Orks in their ramshackle construction, yet possessed a terrifying, uniform lethality.
Countless Clanrats, clad in full flak-armor and wielding long-rifles tipped with Warp-bayonets, glared hungrily at the Hive. To the Skaven, the massive Hive City felt strangely welcoming. It was merely an inverted rat-nest, one that reached for the clouds instead of digging into the crust.
"Yes-yes! Fire! Make the litter-scum fire!"
Hundreds of Warp-lightning Cannons and "Earth-shaker" variants of the Poison Wind Mortar opened fire.
Zzzzt-Zzzzt!
Warp-lightning slammed into the Hive walls. The Lion noted with concern that the Void Shields were fluctuating wildly. He knew the cause: the projectiles were saturated with pure Warp-energy, which not only disrupted the shield's circuitry but threatened to transmute the very matter it touched.
The Imperial artillery batteries fixed their coordinates and retaliated. A rain of Basilisk shells fell upon the Skaven lines, turning their metal-scrap cannons into a sea of fire. Watching the ratmen flee in terror from the explosions, the Astra Militarum raised a premature cheer of victory.
However, their joy was short-lived. Legions of Slave-rats swarmed over the wrecks, salvaging parts with frantic speed. Within mere hours, even more Warp-lightning Cannons were hauled back into position.
Then, the Skaven began their signature maneuver: they started digging.
The flat ground surrounding the Hive was torn asunder by jagged ravines. The Skaven's entire front line and artillery batteries were shifted into these complex, erratic subterranean networks.
"Cursed xenos! They are... they are burrowing into the deep-earth!"
Only those known as Tyrannic War Veterans, accustomed to the burrowing tactics of Hive Fleet Jormungandr, knew how to handle such an assault. The mortal defenders were lost.
Even the Lion found the situation troublesome. Information on this new enemy was sparse; he knew only that they were physically frail, numerically superior, technologically advanced in a crude fashion, and strictly hierarchical.
"Seal every bulkhead and sewer line immediately!" the Lion commanded. "Evacuate everyone from the Underhive. Move them to the Mid-hive at minimum!"
The Dark Angels obeyed without question, but the mortal bureaucrats stammered in concern. "My Lord, the Mid-hive cannot possibly accommodate such numbers!"
The Lion did not dignify them with a look. The Emperor's First Primarch replied with cold indifference: "Surrender your luxury villas and estates. There will be room enough."
He turned and strode away. The Underhive was too complex for even the Astra Militarum to hold, and the Dark Angels were spread too thin. The Lion chose to cede the darkness below to the Skaven, concentrating his forces above.
It was a decision that would prove to be a grave error. For the Lion did not yet know that Clan Skryre's ultimate masterpiece was not the Warp-lightning Cannon, it was the Doomrocket.