64: Chapter 64: The entire Tyrannical fleet charged forward, only to collide with the Void Throat.

The full scope of the Tyranid Hive Fleet "Leviathan" appeared on the edge of the Ultima Segmentum three days after the Void Throat was activated. It was not a vanguard tentacle, nor a flanking probe fleet—it was the main fleet. As the scanners of the Wrath of the Emperor captured its silhouette, the Tech-Officer's hands hovered over the control console, and with a strained voice, they reported the initial readings: the Hive Ship in the very front exceeded the length of any Gloriana-class battleship known to the Imperium. Its hull was not metal, but a living fortress woven from layers of symbiotic chitin and calcified creep. Behind it were dozens of slightly smaller Hive Ships, and on both flanks were densely packed, innumerable cyst-vessels and Spore Cyst deployment arrays. The entire fleet was arranged in the Tyranid's signature devouring formation, slowly pushing toward the Blackstone Defense Line like a writhing, dark purple tide.

Marcus Aurelian stood on the bridge of the Wrath of the Emperor. The restraints on his right hand had been completely removed, and his fingers gripped the edge of the command console once more. He ordered the entire fleet to initiate the decisive battle protocol. All Strike Cruisers of the Third Assault Fleet deployed into a wedge-shaped anti-air formation, Void Shields were charged to their limit, and the Lance Weapon arrays locked onto the dense clusters of the Tyranid main fleet's command neural layers. Captain Oldenburg sent a confirmation signal from Griffin IV; all engines of the Blackstone Defense Line had switched to decisive battle mode, and the Titan-Eater was airborne and standing by. Marcus then pressed the Brood Queen's quantum translator and said in a voice that was hoarse but steady: "Tell the Overlord that the Tyranid main fleet has entered the defense line's strike range. The coalition forces are ready." The Overlord's reply was brief to the point of coldness, consisting of only one line: "Let it crash into the Void Throat."

When the first wave of the Tyranid main fleet's spore cloud spread out in the void, even the cold green light patterns of the Blackstone Defense Line were obscured for half a second. It was not the kind of probing attack that used drop pods to exhaust the defense line as before—it was everything. Hundreds of thousands of Spore Cysts were ejected simultaneously from the abdomens of the cyst-vessels, each carrying symbiotic armor specialized to counter the Blackstone resonance. The Hive Mind had clearly learned a lesson from the total annihilation of the vanguard tentacle; the surface of this batch of Spore Cysts was covered in a layer of genetically modified creep capable of actively absorbing Blackstone resonance. While the absorption efficiency was not high, it was enough to allow them to hold on longer at the edge of the defense line's spore mine dispersal zone.

The Brood Queen crouched beside the base of the Talasta Void Gate, and every Blackstone Resonance Chamber on her adamantium-chitin carapace pulsed in synchronization with the defense line's decisive battle frequency. Her quantum translator broadcast across all coalition channels: "Blackstone resonance-absorbing creep detected on the outer layer of the Spore Cysts. The absorption efficiency is insufficient to penetrate the defense line, but it can buy them more impact windows. I suggest switching the Void Throat's seal frequency from the passive defense layer to active phase countermeasure." Bern, holding his Holy Hammer at the main entrance of the Void Gate, looked up after hearing this to confirm that the energy release of the active countermeasure would temporarily weaken the Void Throat's sealing shell, and asked the Brood Queen if the window would be long enough to repel this wave. After the Brood Queen answered, he hoisted the Holy Hammer onto his shoulder again and ordered the entire Grey Knights squad via the communication channel to enter the Void Gate base position, with Holy Hammers charging in sync.

After the Brood Queen's command was issued, the three rings of the Void Throat's cold green light accelerated their rotation in synchronization. Thousands of hexagonal resonance chambers unfolded layer by layer from the spherical quantum state array, firing the master frequency of the Old Ones' seal, the quantum encrypted shell of the Necron Dynasty, and the living neural random transformation algorithm injected by the Brood Queen in a synchronized phase, slamming violently into the spreading spore cloud front. The layer of Blackstone resonance-absorbing creep covering the surface of the Spore Cysts was completely stripped away the moment it made contact with the Void Throat's active countermeasure. The dark purple mycelium was ignited in the void by the cold green light patterns, bursting like charred blood vessels all at once. Having lost their symbiotic armor, the entire spore cloud front was directly exposed to the defense line's spore mine dispersal zone. The trailing cyst-vessels attempted to urgently retract their Spore Cyst deployment arrays, but the Titan-Eater had already cut in from the right side of the gravity reef, its four piercing bone blades tearing open the symbiotic chitin on the flank of the first Hive Ship in the void.

Sebastian's Terminators assault platoon and Bern's Grey Knights squad engaged in hand-to-hand combat with the Tyranid tentacles that had broken through the defense line at the base of the Void Gate. Every time a Holy Hammer crushed the skull of a Tyranid beast, the silver light left a resonance scar on the cold green sealing ring. After the Titan-Eater tore open the third Hive Ship, the Void Throat's active countermeasure completely stripped the Tyranid main fleet's command neural layers from the core sector of the defense line, and the remaining Hive Ships began to collide with each other after losing the coordination of the Hive Mind. Marcus ordered the entire Third Assault Fleet to counterattack, and the Lance Weapons and Leviathan railguns fired in unison, chasing the retreating Hive Ships. Oldenburg extended the defense line from the Talasta Void Gate to the perimeter of Griffin IV, with all engines of the Blackstone Defense Line maintained at full power. The coalition forces took less than one standard hour to push the Tyranid main fleet completely back into deep space from the edge of the Ultima Segmentum.

After the defensive battle, the sealing rings of the Void Throat maintained a low, humming drone from their initial operation. The Brood Queen translated the master control logs of the Titan-Eater after it returned home for Marcus to see. After confirming that the Void Throat would continue to serve as a decisive weapon in higher-dimensional counterattacks, Marcus sent a summary of the decisive battle report to Terra in the name of the coalition Commander. At the same time, he forwarded the protocol copy left by Nephilak on the Eternal Echo, indicating that the Void Throat, under the joint command of the coalition forces, had successfully annihilated the Tyranid main fleet Leviathan, and that the Blackstone Defense Line and the Void Throat defense line remained active and on alert. After sending the message, he leaned against the command console and said hoarsely to the Brood Queen's translator: "Tzeentch still owes us a crowbar; the fact that the Tyranid main force has been pushed back doesn't mean the war is over. The next ones to come will probably be new strains personally crafted by the Tyranid Hive Mind." The Brood Queen only replied with one line: "The Overlord says, let them come. The Void Throat's seal suite has already recorded the complete signature code of the Tyranid command neural layers. When its next batch of new strains hatches, The Swarm will taste them first."