"The humans know you're coming, Zehaka. They'll throw everything they have to stop the train. Try not to die."
"Yes, my Lord."
The Overmind focused his consciousness on Zehaka. Dehaka, as a pure Primal Zerg, did not share a direct visual link with the Hive Mind, leaving his progress a mystery for the moment. But there was no rush; if Zehaka's "Swarm-born" variant was performing this well, the original Pack Leader was likely doing even better.
On Volkus, the Imperial Air Force had ceased its direct strafing runs after the Primal Mutalisks tore through their wings. However, they remained at a distance, their high-altitude auspex arrays tracking the massive railcar's every move.
In a fortified command room, local garrison commanders and Imperial officers were locked in a heated debate.
"We should use the Great Volkanon itself!" one PDF officer shouted. "Target the tracks ahead of the train! If we destroy the rail, the cars can't reach the loading chamber."
"Are you insane?" an Astra Militarum Colonel retorted. "These xenos have legs. They're using the train for speed, but they aren't bound to it. If we destroy the route, they'll just scatter into the city. Fighting a Titan-sized beast in the open streets is a nightmare; fighting it in the tunnels is suicide. We need to funnel them."
The rail line passed through several massive transit checkpoints. Each was guarded by blast doors that would take a Titan hours to breach, bristling with heavy weaponry and garrisoned by thousands of troops. It was the ideal killing ground.
"And if they breach the gates?"
"If the Great Gates fall, then the city is already lost."
The argument dragged on until a high-ranking Inquisitor from the Ordo Xenos slammed his fist onto the table. The room fell silent.
"Enough. We deploy at the Great Gate of the Mid-Hive. The terrain allows for maximum fire concentration. We stop them there, or we don't stop them at all. Furthermore, we will not wait for them to reach us."
"My Lord?"
"The Sisters of Battle and the Storm Troopers will launch a high-altitude boarding action. They will strike the rear of the train, preventing the xenos from retreating and thinning their numbers before they hit the gate. And be prepared—the Ultramarines are en route."
The Imperial war machine moved with a rare, desperate efficiency. Defensive lines were drawn at the gate, while several squads of the Adepta Sororitas—Battle Sisters clad in sanctified power armor—prepared for insertion. Accompanying them were the "Storm Eagles," elite Harakoni-style drop troops equipped with grav-chutes and jetpacks. Though they lacked heavy tanks, their melta-bombs and krak-missiles were designed to crack open the toughest hides.
Ahead of the train, the Great Gate loomed, its walls lined with naval-grade defense cannons. Focus-firing those batteries could bring down a Warlord Titan. Against a standard Zerg vanguard, this defense would be impenetrable.
But Zehaka was no standard Zerg. He was a cunning hunter, and his "infantry" were the size of Dreadnoughts.
High above, Valkyrie gunships banked through the smog. The Battle Sisters and Storm Troopers descended, landing on the rear cars of the moving munitions train. As their boots hit the metal, they realized they weren't stepping on plasteel.
They were stepping on the Creep.
The writhing, purple biomass made the Sisters scowl in disgust, but they didn't hesitate. They moved toward the front of the train, their bolters raised. They hadn't gone far before the environment shifted. The air within the railcars was thick with a hazy, spore-laden mist.
"Helmets on! Sealed environments!" the Sergeant barked. "The air is toxic!"
The soldiers snapped their visors shut. It was a life-saving move; the spores were a concentrated strain of the Hyper-evolutionary Virus. Zehaka had anticipated that humans often preferred to feel the "holy air" of battle on their faces—a habit that had already cost a fifth of the PDF their lives through silent infection.
"So, you've arrived," Zehaka thought, sensing the vibrations from the back of the train. He didn't turn around. These intruders weren't worth his personal attention.
The Imperial troops pushed deeper, warily scanning the shadows, unaware of the threat beneath the floorboards.
CRACK.
A massive, bone-chitin spike erupted through the reinforced floor of the railcar. It impaled a Battle Sister through the midsection, hoisting her screaming into the air.
"Contact! Beneath us!"
The Storm Troopers opened fire on the floor, but the Primal Lurkers weren't directly beneath them. Lurkers sense prey through ground vibrations and strike from a distance. As the soldiers scrambled, a second spike erupted, skewering a Storm Trooper.
"Cease movement! Don't move!" the Inquisitor shouted over the vox. "They track by vibration!"
The group froze. The attacks stopped instantly. Silence returned to the car, broken only by the hum of the maglev engines.
"How do you know their traits, My Lord?" a Sister whispered.
"The Ordo Xenos has encountered this 'Swarm' before," the Inquisitor replied grimly. "They are the Zerg. And they are learning our ways as fast as we learn theirs."