As time passed, the war on the front lines raged on. The Tyranid swarm, devoid of the concept of rest, launched frenzied assaults against all defensive perimeters.
Facing the suicidal attacks of overwhelming numbers of Banelings and Scourges, as well as the dense bombardment from Siege Tanks, the Tyranid Hive Mind chose to alter its tactics. It first reduced the number of melee Tyranids and began hatching large quantities of Biovores and other over-the-horizon long-range units.
Simultaneously, it intentionally dispersed its frontline melee units. Often, a Tyranid Synapse creature would lead a small pack of lower-tier organisms. Upon encountering the enemy, they would use their lives to stall the foe's advance, allowing the plasma-lobbing artillery units to conduct precision strikes.
Meanwhile, the number of Tyranid aerial units was maintained at a level just sufficient to match the Zerg Swarm's air force. The Hive Mind had discovered that a massive network of Missile Turrets had been gradually deployed behind the human lines. The most "monstrous" trait of the Terran SCVs was their ability to scrap metal into a brand-new Missile Turret on the spot.
This led to a recurring pattern: just as a swarm of Tyranid flyers destroyed a turret array, waves of SCVs, under the cover of PDF legions and Goliath wings, would rebuild the array using the wreckage. They required very little new material; the scrap on the ground sufficed.
Realizing this, the Tyranid Hive Mind abandoned the strategy of harassing the human rear, as it was meaningless. The endless turrets could never be fully cleared, and the Hive Mind was merely losing biomass—biomass that was essentially being gifted to the enemy.
If the Tyranid swarm had previously advanced through ferocious aggression, it was now shifting to a strategy dominated by heavy long-range fire, slowly squeezing the humans' living space.
Moreover, the Hive Mind began using large numbers of Mawlocs and Trygons to bypass the Creep-covered plains and bunker complexes to strike supply convoys in the rear, aiming to reduce the intensity of frontline fire.
To counter this, Colton had to divert significant numbers of PDF troops and tanks to escort the convoys, forcing a portion of the Siege Tanks away from the front.
Zagara was no fool either. She learned from the Tyranids, breaking up her high-density frontline forces and hiding Banelings and Scourges within small, scattered Zerg units. When encountering a Tyranid Synapse creature, the Banelings would suddenly emerge under the cover of other Zerg to deliver a fatal blow. As long as they were fast enough, they could escape the subsequent bombardment.
Logistically, facing the numerical gap between the Zerg and the Tyranids, Abathur began enhancing the main Zerg forces in batches.
He first evolved the secretory systems of the Roaches, developing bile ducts that allowed them to spit hydroiodic bile. Any light enemy units—such as Hormagaunts, Termagants, or Rippers—that touched this bile would instantly melt into puddles.
However, the Tyranid Hive Mind noticed this immediately and strengthened the thickness and coverage of the chitinous carapaces on its Gaunts. Though this increased biomass consumption, it effectively reduced casualties against Roaches.
Seeing this, Abathur initiated a second enhancement for the Roaches. He introduced a massive amount of microorganisms into their bodies. These microbes, living symbiotically with the Roach, gave their saliva a unique side effect: any enemy touched by it would suffer slowed movement, mechanical failure, and weakened attacks.
He also embedded parasite eggs within the Roaches. These eggs would enter the enemy's body through wounds corroded by acid, quickly hatching and bursting forth, creating a "sea of insects" that charged back at the Tyranid army.
As Alexei expected, the Tyranid Hive Mind iterated again. It strengthened the Phage cells within all Tyranids, allowing them to destroy any non-self biological invaders at maximum speed. Additionally, it coated the Tyranid carapaces with a special mucus that neutralized the acidity of Zerg acids, minimizing the negative effects.
Realizing that biomass shouldn't be spent solely on Roaches, Abathur turned his attention to the Hydralisks. Since weakening the enemy was failing, he would strengthen his own.
He drastically increased the Hydralisks' adrenaline levels and programmed them to voluntarily sever the Hive Mind's control upon entering combat. This plunged them into a state of endless frenzy, greatly increasing their attack speed. He also modified their forelimbs to fire bone needles simultaneously, significantly boosting their firepower.
Similarly, after consuming vast amounts of Zerg, the Tyranids were undergoing terrifying mutations. Gene fragments from Banelings and Scourges enhanced the destructive power of Tyranid long-range units. The powerful regeneration genes from Roaches allowed Tyranids to heal by consuming enemy biomass. As long as they weren't killed instantly, they could slowly recover, making them even harder to put down.
Both swarms were in a frenzy of evolution and iteration, constantly seeking the other's weaknesses and consuming them to bridge their own gaps. Evolution and consumption were the shared themes of both sides.
In the Zerg Hive, Alexei stood before a massive cheek pouch. This was the product of Roach evolution: the Ravager.
As the pouch burst, a giant Zerg—three times taller than a human in CMC power armor—appeared before him. He stepped back to take in the full view. It looked like an upscaled Roach, but its back had transformed into a giant, lumpy glandular organ, with skin of vivid orange-red and yellowish-green, making it look hideously ferocious.
This special organ allowed the Ravager to store large amounts of high-temperature plasma. When encountering enemies, the Ravagers would act like mortars, launching globs of Corrosive Bile from their backs.
This bile could hit aerial targets, and its impact was so powerful that even the defensive force fields of Protoss Sentries could not withstand it. The only drawback was the long "wind-up" before firing, making it dodgeable for alert enemies.
Alexei circled the "Fire Roach," observing it closely. This would fill the Zerg's void in over-the-horizon attacks. He immediately ordered mass production of these Ravagers, planning to deploy them to the front lines only once their numbers were sufficient. Deploying them in small batches would only allow the Tyranid Hive Mind to adapt and evolve too quickly.
Furthermore, regarding the Tyranids' current strategy of long-range stalemates and slow advances, he had an idea.
The bulk of the Tyranid main force was currently concentrated on the Cinder Plains. They realized that behind this defensive line lay the human heartland; the swarms elsewhere were merely feints. Breaking this line would mean final victory.
This meant that if he could deliver one massive blow to this group, he could harvest an enormous amount of biomass while effectively thinning their numbers.
Given the Tyranids' massive long-range numbers, if the Zerg could force a close-quarters engagement, they would undoubtedly prevail again.
Alexei looked down at his interface at the biological entity—or rather, the structure—that represented the Zerg's largest ground unit. Just bringing it onto the battlefield would require biomass equivalent to an entire Zerg swarm. The previous victory had given him the confidence to do so.
"You aren't the only ones who can dig tunnels, Tyranids," Alexei whispered to himself. He was preparing to wrap them up like a giant dumpling.