How Zombies Survive in the Apocalypse

“…An immense number.”

Observing the zombies surging from the darkness, Aiden muttered under his breath.

From his vantage point atop the 20-story building, he had an expansive view that even allowed the buildings in the distant city center to be seen several kilometers away.

But nearly half of that wide field of vision was filled with zombies.

Not just the western direction Aiden was focusing on, but the zombies’ presence also stretched towards the northern mountains.

And to the south, while still far off, the undead were engulfing the city as well.

Their encirclement literally blanketed the entirety of Phoenix.

The sheer length exceeded 20km.

The number of zombies mobilized for this was simply uncountable.

At minimum, hundreds of thousands.

The scale clearly exceeding Aiden’s expectations prompted a brief grunt from within his helmet.

“They’re getting closer.”

The vanguard of that zombie horde had finally reached the vicinity of the apartment Aiden’s group had occupied.

The four-lane road in front of the apartment was packed densely with corpses.

The undead could be seen mindlessly passing over it in disarray.

But the zombies showed no intention of entering the building itself.

They merely swept through the streets like a massive tidal wave.

“…”

From within the apartment that would soon be buried in the midst of that procession of corpses, Aiden tried to locate Fear amidst the zombies.

However, Fear’s figure was nowhere to be seen.

Not that it was unexpected.

That mutant leading this zombie horde would currently be located somewhere within the vast expanse of Phoenix.

To hope that such a creature would readily appear within Aiden’s line of sight was simply leaving it to chance.

At this rate, there was no telling when he might encounter Fear.

But it was right at that moment.

The booby trap Aiden had prepared exploded.

Boom!

A momentary flash accompanied by a thunderous explosion erupted from the apartment’s first-floor entrance.

It seemed an unfortunate zombie that had been swept off the road and wandered to the entrance had triggered the trap.

Grenades had been rigged to that booby trap.

Thanks to that, the zombies within a radius of ten-odd meters from the apartment entrance were instantly reduced to shredded meat.

That detonation and ensuing chaos caused the zombies’ dull, vacant eyes to glint with frenzy.

They began surging towards the apartment.

“So it begins.”

Accompanying Aiden’s mutter, another explosion rang out.

The pre-installed traps Aiden had set.

With each detonation, those traps consumed dozens of zombies at a time.

But the noise and flames only drew even greater numbers of the undead.

“Kiiiii!”

“Uwoooooh!”

Soon, the surrounding corpses swarmed in a black tide towards the apartment’s vicinity.

While mutants were among them in no small number, none could immediately reach the upper-level defensive lines of the apartment.

Not solely due to Aiden’s traps, however.

No matter how many traps he had set, they could never rival the sheer numbers of those zombies.

It was the apartment’s narrow structure, not designed for such large-scale traffic, that was causing a bottleneck effect for the creatures.

A Bigfoot’s massive frame could be seen wedged in the entrance, unable to advance or retreat.

“…Still no sign of this Fear?”

Observing the zombies below, Arian asked with a hint of restlessness.

While the fierce onslaught had been considerably weakened by having to pass through the narrow corridors, thankfully,

it was only a matter of time before the zombies reached their defensive positions.

“This has only just begun. Stay calm and wait.”

“But…”

Arian furrowed her brow slightly.

They had entrusted the apartment’s defenses to the other people.

But among them was Sadie as well.

She couldn’t help but feel uneasy about leaving the rear guard solely to them.

Letting out a gloomy sigh at Arian’s words, the truth was that Aiden shared the same apprehension.

No matter how many layers of barricades they had constructed, no matter how much firepower they had armed that location with, variables could still arise.

Especially if mutants were present, such variables were difficult even for Aiden to foresee.

And among the zombies now trying to force their way into the apartment, mutants could already be easily spotted.

Moreover, with their path obstructed, those creatures were conveniently standing still like perfect targets.

This was an opportunity Aiden couldn’t easily let slip by.

So he decided to exercise a degree of flexibility.

“Can you operate the scope?”

“Of course. But why?”

“You search for it. I’ll provide support from here against the ones entering the apartment below.”

Aiden entrusted the scouting to Arian.

In the meantime, he would snipe any mutants that breached into the apartment from the rooftop.

With Arian’s superior senses, this wasn’t an unreasonable allocation of roles.

Arian immediately nodded in understanding.

“Got it. But what exactly should I be looking for?”

“…Brutals.”

At Aiden’s words, Arian tilted her head slightly in puzzlement.

She had already spotted a few of those tyrant-like mutants earlier.

But Aiden’s next words followed.

“It’s said to move around with other mutants as bodyguards.”

That was one of the pieces of information Aiden had obtained about Fear.

“It’s different from the Commander I saw in Pittsburgh. It’s likely a creature that knows how to protect itself. So it will undoubtedly move together with Brutals.”

“So… I just need to find where multiple Brutals are clustered together?”

Arian summarized, and Aiden nodded as he added.

“But don’t rush. It will likely be quite cautious as well. It may not show its face for quite a while.”

“What… you mean it might not appear at all?”

“Not quite.”

Aiden extended his sniper rifle towards the area below the apartment.

Through his scope, the head of a Hedgehog could be clearly seen.

“No matter how powerful the mutant, this is a place it cannot recklessly charge into. Even if that weren’t the case, I’ll make it seem that way.”

“…”

“Which means, for the zombies to breach this location, they will inevitably require intelligence. The intelligence to circumvent traps and deploy elite strike forces. For that alone, it is bound to reveal itself.”

Bang!

Aiden’s rifle discharged.

The Hedgehog that had been trying to enter the apartment had its head blown apart, its body immediately going limp.

But wedged amidst the masses of zombies, the fallen Hedgehog didn’t even collapse.

Its corpse merely obstructed the flow like a buoy stuck in the middle of a crowded subway.

“So it will definitely appear. Don’t let your guard down.”

At Aiden’s words, Arian nodded slightly with a tense expression.

Immediately taking up the scope, she continuously scanned every nook and cranny of the view she had previously been unable to see.

And before long.

Tatatatatatata!

The savage roar of machine gun fire echoed from the lower floors.

It meant the zombies that had finally breached into the apartment had reached the defensive lines.

* * *

“Here they come again!”

At the first defensive line on the staircase leading to the 14th floor of the apartment.

It was the machine gunner Sophia who shouted those words.

The 2.5-meter wide staircase, which had only gathered dust until just before, no longer looked the same.

The glass wall in the direction the machine gun was aimed had been completely shattered without a trace.

And the furniture that had previously blocked the staircase below had been smashed beyond recognition.

But more gruesome than anything were the scattered chunks of rotten flesh coating the area around those stairs.

Tatata-!

The machine gun mounted on its stand trembled like an earthquake as it spewed gunfire.

The zombies that had been climbing those stairs were instantly shredded and torn apart by that merciless hail of steel, further splattering their flesh in all directions.

How many had it been by now?

She hadn’t counted from the start, but it felt like it had surpassed hundreds already.

And still, there were many zombies remaining.

Having witnessed the spectacle outside herself, she was all too aware of that fact.

“Heh, I was wondering how this would go at first…”

Sophia muttered quietly as she continued firing the machine gun.

In truth, when she had first come face-to-face with the staggering number of zombies passing by outside the building, it had felt utterly hopeless.

She had thought there was no way they could survive amidst those hordes.

She had regretted numerous times that they should have fled, no matter how recklessly.

But now, having directly clashed with those creatures, her thoughts had somewhat changed.

Unexpectedly, the battle was manageable.

Above all, the first line of defense she was guarding remained sturdy.

A Wielder had managed to force its way up earlier, but even that mutant was merely a mass of meat before the machine gun’s firepower.

So if they could just endure like this… perhaps they really could survive.

Sophia had that thought when suddenly,

Her finger on the trigger felt unnaturally light.

Instead of the satisfying gunshot, what followed was an empty metallic click.

It was only then that she realized the ammunition belt containing hundreds of rounds had been completely expended.

“Machine gun! We need to reload!”

Sophia shouted.

At that, the people who had been behind and beside her stepped forward.

While the machine gun fell momentarily silent, they drew their rifles towards the zombies that continued climbing up.

“Where are the machine gun ammo cans?”

“Here! I just brought them.”

A child who had run down from the upper floor handed Sophia a large ammunition box.

Sophia accepted it, inwardly surprised.

It was a considerably heavy weight for the girl, who looked to be only around 10 years old, to be carrying.

Sadie, if she recalled correctly.

Sophia briefly watched the panting child who had hurriedly brought it.

But Sadie showed no signs of strain as she handed it over and immediately headed back upstairs.

After watching Sadie with an impressed gaze, Sophia snapped back to attention.

Clearing the spent ammunition belt from the machine gun, she loaded the new box magazine this time instead.

While their loading mechanisms differed slightly, Sophia easily reloaded the machine gun.

Ting!

But then, a sharp ‘ping’ sound reached Sophia’s ears.

Not from a zombie, but someone’s stray bullet.

Furrowing her brow, Sophia shouted a warning.

“Don’t shoot at the wall! Watch your muzzles! I almost got hit!”

After cautioning those firing rifles, Sophia gripped the machine gun once more.

By now, a reddish glow had formed around the machine gun’s barrel.

It was overheating.

Did she need to pause firing for a moment?

But unfortunately, Sophia wasn’t afforded that luxury.

“Grruuuu!”

The sudden zombie moan from below caused her eyes to widen.

It was the unmistakable roar of a mutant, distinct from regular zombies.

Moreover, it was the cry of a monster Sophia had encountered before.

“Damn… it’s a Brutal!”

Accompanying Sophia’s shout, a resounding Bang! shook the building.

The Brutal, confined within the narrow zombie-packed corridor, was throwing a tantrum laced with impatience.

It didn’t leave even its kin obstructing its path unscathed.

Twawack!

The Brutal’s monstrous strength mercilessly trampled the zombies that had been climbing the stairs.

The tremors it caused could be felt gradually approaching.

At this, Sophia released her grip on the machine gun.

A Brutal was a monster that couldn’t be driven back even by this machine gun’s fire.

That was something Sophia, who had once narrowly escaped death from a Brutal, understood all too well.

That’s why she immediately recalled the instructions Aiden had given.

“Fall back!”

The personnel defending the barricade retreated from the stairs into the apartment’s inner corridor.

There, they immediately entered the adjacent room, which contained several detonator switches connected in a line.

All of them were pre-installed explosives.

Bang!

The building shook again.

Thanks to the Brutal’s reckless advance, its location could be clearly estimated.

Directly below, on the 13th floor.

Without hesitation, Sophia pressed the detonator switch corresponding to that floor number.

Accompanied by an ear-ringing explosion, the sound of countless shrapnel fragments ricocheting from the stairwell area followed.

Claymore mines.

The hundreds of steel balls exploded along with the blast, violently tearing through the confined staircase.

“Grraaaaahh!”

Even so, the Brutal didn’t fall silent.

With parts of its face and outer skin shredded, exposing the solid muscles beneath and even the bone, it endured the full force of the Claymores, just as it had in that hotel in Pittsburgh, refusing to collapse.

“…”

But Sophia didn’t show a hint of emotion despite witnessing the Brutal’s resilience.

That toughness was something Aiden, who had installed these explosives, hadn’t overlooked either.

Boooooom!

Immediately after, the second set of explosives connected to the detonators erupted.

The Brutal, which had withstood a single blast, finally succumbed before the successive detonation that followed.

“Uwooooh…”

The Brutal’s body, with its limbs torn asunder, collapsed on the spot.

Confirming the mutant’s movements had ceased, Sophia returned to the barricade.

Although the explosion had occurred on the lower floor, the shockwave that had swept through the stairwell left considerable impact.

Shrapnel fragments were embedded all around the barricade Sophia and the others had been defending.

Had Sophia remained there, she too would have been caught in the blast.

But that wasn’t the issue.

Some of the fragments seemed to have struck the gun barrel, damaging the machine gun.

Seeing this, Sophia clicked her tongue in frustration.

With only rifles instead of the machine gun, there would be limitations in defending the barricade.

While regular zombies could still be held off, any mutants impervious to rifle fire would be impossible to stop.

“Pass word that we’ll likely have to abandon this barricade soon.”

“Understood.”

At Sophia’s words, one of the women ran down the corridor.

When abandoning this position, the personnel guarding the opposite staircase would also need to retreat together, hence the message being relayed.

“…”

In contrast to her earlier brimming confidence, a hint of unease now flickered in Sophia’s eyes.

The defensive line that had seemed so sturdy was ultimately breached.

“Uwoooooh!”

Once again, the cry of a mutant echoed from below.

This sound was… likely a Hedgehog, perhaps.

Another creature difficult to contend with using just rifles.

“No choice. Everyone fall back.”

With no other option, Sophia ordered her forces to retreat upwards to the defensive position on the 16th floor.

She too gathered what supplies she could carry.

It was then that the heavy footsteps of the Hedgehog could be heard approaching from below.

Sophia ran up the stairs.

And from her pocket, she retrieved something.

Another detonator switch.

Soon after, the entire 14th floor barricade erupted, engulfing the Hedgehog.