The library's entrance, writhing like a living entity in dark green, resembled an unhealed wound, silently mocking their plight. The air was thick with a sickly sweet stench of decay, mingled with the acrid smell of scorched vines from energy weapons and the pungent chemical odor from Rick's corroded protective suit, forming a nauseating aftermath of battle.
Rick slumped to the ground, his body still trembling uncontrollably. Morgan roughly tore open an emergency kit and sprayed a large dose of radiation-neutralizing gel and disinfectant foam onto Rick's almost bare calf, eliciting a stifled groan of pain. In this environment, a damaged protective suit was nearly a death sentence; even with immediate treatment, subsequent radiation sickness was almost inevitable.
"Can you walk?" Captain Barton's voice was emotionless, like steel striking steel.
Rick's face was pale, sweat rolling down his forehead. He gritted his teeth, trying to stand, but staggered. "I… I need time… my leg muscles might have been burned by the corrosive sap…"
Lina checked the energy cell of her pistol, interjecting coldly: "Time? Captain, the radiation dose here every minute is enough to give someone in a safe zone a month of disability allowance. Our earlier commotion was like a concert — any 'neighbor' with ears within ten kilometers is probably on their way to greet us."
She wasn't wrong. The yellow dusk was quickly giving way to a deeper navy blue. Night was the domain of the irradiated beasts. Their senses were sharper in darkness, their activity more frequent and frenzied. Staying on the open streets was tantamount to suicide.
Ethan's gaze swept over the twisted, vine-engulfed buildings around them. He pointed to a five- or six-story apartment building diagonally opposite. It was also covered in vines, but the main structure seemed relatively intact. Its elevated position above street level, with an entry ramp that was easy to defend, made it ideal.
"That building. Third to fifth floor. The view is relatively open, only one main staircase for defense. The vines don't seem to have fully penetrated inside," Ethan said quickly. "We need to establish a defensive point at height and survive the night."
Captain Barton considered for only a second. "There. Morgan, carry him. Lina, Ethan, alternate covering fire. Move!"
The team moved again, slowed by Rick's injured leg. Each step felt like trudging through a sticky nightmare. The darkened windows and gaps along the street seemed like countless hidden eyes, watching them from the deepening twilight.
They laboriously ascended the apartment steps, prying open the rusted metal security door. Inside was a dim hall, scattered with rotting furniture and debris. The thick dust was heavy in the air, but reassuringly, the number of live vines had significantly decreased. Only a few thin, nerve-like tendrils emerged from ceiling and wall cracks, swaying slightly.
There was no time for meticulous clearing. Barton quickly issued orders: "Sweep the first floor, block all secondary entrances. Morgan, establish the first defensive line at the stairwell. Lina, Ethan, come with me to the top floor and set up a circular defense. Rick, find a room on the second floor, repair communications, attempt to capture any signal, and monitor life and energy readings."
The team moved silently. Morgan stationed the heavy rotary gun at the end of the corridor facing the staircase, his massive frame like a boulder blocking the main path upstairs. Lina and Ethan quickly swept up the stairs, ensuring each floor had no major beast nests or dense vine growths.
Finally, they reached the top floor. It appeared to be a luxury apartment, spacious and with excellent visibility. The large floor-to-ceiling windows were almost all shattered, leaving only twisted metal frames resembling skull eye sockets, facing the dead city below and the library where the scientists' trail had ended. The cold wind blew freely, carrying faint, unsettling wails and rustles from the distant ruins.
They chose a room with the best view, backed against a load-bearing wall, as their stronghold. Barton and Ethan quickly piled heavy furniture and concrete fragments at doors and windows to form improvised cover. Lina pulled a few inconspicuous small discs from her gear bag — miniature vibration-sensitive mines — and skillfully placed them at stairwells and vulnerable windows.
"All set. The 'welcome party' invitations have been sent," Lina said, patting the dust off her hands with a grim curve to her lips.
Night had fully fallen.
No moonlight, no starlight. Only an endless, suffocating darkness blanketed the decaying city. Sporadic phosphorescence from mutated plants and fungi flickered like ghostly flames among the city's carcasses, adding to the eerie atmosphere.
Temperatures dropped sharply. The cold came with high-intensity radioactive dust, like icy needles trying to pierce protective suits and reach their bones.
The four gathered in the top-floor room. Morgan stayed downstairs, his comm channel silent, only faint metallic sounds revealing the steel barrier's presence. Rick was in a second-floor room, illuminated by the faint glow of his portable device, his pale, focused face tense as he fought against intense energy interference, attempting to capture any useful signal.
Ethan leaned against a window barricade, observing the dead world outside through night-vision goggles. Everything was bathed in a greenish, eerie hue. The broken city outline resembled a giant skeleton's spine, and the slowly writhing vines clung like deadly parasites. The wind carried grotesque wails and shrieks through the hollow buildings, masking any other sounds in the darkness.
Time passed slowly under extreme tension.
Suddenly!
A faint sound, like nails scratching glass, mixed with the wind, drifted from afar.
Ethan tensed instantly, adjusting the night-vision focus to locate the source. Lina snapped her head up, sharp-eyed, hand on her pistol.
The scratching stopped.
A few seconds later, another sound emerged. Low, like something deep underground… a whimper? Or the labored breath of a massive lung. Intermittent, direction hard to pinpoint.
"Did you hear that?" Lina whispered through the internal channel, her voice barely audible.
"Yeah." Ethan replied simply, all attention on listening and observing.
Captain Barton joined the window, not using night-vision, his eyes sharp from countless life-or-death experiences. Experience told him that some dangers elude instruments.
Silence returned, filled with tension, like a drawn bowstring.
Then, the sounds became clearer and more frequent.
Scratches from multiple directions, as if something moved swiftly on the building exterior and nearby streets. Low whimpers became guttural, threatening rumbles. The faint sound of claws on gravel could be heard.
They were coming, in numbers.
"Multiple life signals detected moving!" Rick's frightened voice broke the silence from the second floor. "Spread out, moving fast! Surrounding the building! Radiation readings rising! It's a pack of beasts!"
Almost simultaneously, Morgan's calm, low voice came from below: "Prepare for contact. Stairwell. Unknown numbers."
The three on the top floor took combat positions. Barton and Ethan held the window, aiming at potential street threats. Lina ghosted to the stairwell above, pistol trained on the dark corner below, forming crossfire with Morgan.
Yet, the expected frenzied assault did not occur immediately.
The sounds — scratches, rumbles, footsteps — slowed within a certain perimeter around the building, becoming a slow, rhythmic… circling.
They did not attack instantly but circled like patient, experienced hunters. In Ethan's green-tinged vision, he glimpsed rapid, distorted shadows darting behind cover, faster and more grotesque than the daytime "Burrower Hounds," yet never exposed to fire for long.
This eerie, oppressive circling lasted nearly ten minutes — an eternity for the tense team.
"What the hell are they waiting for?" Lina muttered impatiently.
Suddenly, all sounds — scratches, footsteps, rumbles — stopped at once.
Absolute silence fell again, more terrifying than before.
Amid this suffocating quiet, a new sound arose.
At first faint, like a high-frequency hum beyond human hearing. Soon, it intensified with complex rhythm and variation. It no longer sounded like meaningless noise but… a language? A sequence of sharp hisses, low vibrations, and short bursts — an incredibly bizarre sonic pattern.
The sound came from all directions simultaneously, as if the entire pack "sang" in unison.
"Soundwave attack!" Rick's terrified voice screamed over the channel. "Just like the note said! But stronger! More complex… impossible! It's encoded information!"
High-frequency waves penetrated walls, drilling into helmets, stimulating eardrums and nerves. Even through protective suits, dizziness, agitation, and inexplicable fear and frenzy began to grow.
"Hold!" Barton shouted, cold sweat at his temples. This attack method exceeded his experience.
Ethan clenched his teeth, forcing himself to analyze. The waves weren't uniform; they adjusted. When the waves passed over Lina's vibration mines, certain frequencies slightly intensified. Passing over Morgan's stairwell, bursts of probing sounds were added.
They weren't indiscriminately hissing.
They were using sound to communicate and… scout.
They were scanning the building's defenses, locating fire points, observing reactions.
The thought chilled Ethan to the bone.
"Not an attack!" Ethan shouted into the internal channel, over the eerie waves. "They're scouting! Lina, your mines are marked! Morgan, your position is being probed! They're seeking weak points!"
Almost immediately, the waves stopped for a minute, confirming Ethan's assessment.
Then, the real attack began.
But their approach was unexpected.
No frontal charge, no stair assault.
First impact hit the building's rear flank, partially covered with vines, the seemingly stable first-floor wall!
With a massive, teeth-grating crash and crumbling concrete, the building shook.
"Flank! They're hitting the lower wall!" Morgan's voice trembled slightly.
From above came dense, skin-crawling scratching! Something scaled the building's exterior rapidly!
"Roof! They're climbing up!" Lina turned her aim upward.
Diversion! Coordinated assault!
These creatures had intelligence, even basic tactical coordination!
"Morgan, hold the stairwell! Don't let them through! Lina, Ethan, deal with the roof!" Captain Barton commanded coldly, holding the window, eyes on potential street threats.
"Bang! Crash—!"
A window previously blocked by furniture exploded open! A massive, terrifying head, covered in bone-like armor, protruded, crimson compound eyes glinting with malice.
The battle erupted fully.
Lina's pistol roared, energy beam hitting the monster's eye, splattering viscous fluid. Ethan's rifle fired short bursts at its claw on the window frame, pushing it back.
But more windows were breached! More shadows flooded in like a tide!
Gunfire, snarls, crashes, structural groans filled the top floor!
Amid the chaos, Ethan's sharp hearing detected the distorted sound waves again — short, sharp, rapidly varying — like an invisible conductor orchestrating the deadly siege.
These beasts were not mindless.
They were a hunting pack with terrifying collective intelligence. And tonight, they revealed perhaps just the tip of the iceberg.