Mercenary Black Mamba

Like tackling the lower torso of its opponent, the huge African plate subducted below the lower half of the smaller Arabian plate. Since the Eurasian plate was standing firm behind it, the Arabian plate inevitably became folded in the process.

A rumbling sound could be heard.

The Arabian plate was pushed up. The p-wave reaching the surface 2.5 seconds later (at the speed of 5 to 8 km per second) and the s-wave arriving four seconds later were only about 4.8 in the earthquake scale, but the actual scale affecting the Arabian plate in the depths of 15,000m easily exceeded 9.5.

The Hollow Earth's base was the Arabian plate stuck between the Eurasian and African plates. There was simply no way that the eggs would remain unscathed when their nest was violently overturned. The history of destruction that took place eons ago was recreated on this very day.

Its target was the delicate 'niche' that managed to survive until now since the fall of the Concretus civilization – the Hollow Earth.

Magma began gushing out from the rift that opened up at the bottom of the lake.

The unleashed magma pushed aside the lake water and exploded up to the ceiling of the cavern. The massive pillar of fire rising up began raining down on the lake next.

The massive ancient reptile swimming around with its head out on the surface freaked out and hurriedly submerged itself. To a creature that had relied on the colony of bacteria emitting faint blue light, the explosion of such a bright light was nothing short of an absolute disaster.

Magma boasting 1,200℃ met the water at normal temperature, resulting in an intense reaction. Vicious explosion noises were immediately followed by an incredible quantity of hot steam. The rapidly-expanding steam pressure forced the lake water to shoot up and the thin atmosphere began whipping about like tornadoes.

Magma broke through the shattered stratum to gush out from various locations. Meanwhile, the incredibly hot magma at the bottom of the lake evaporated the lake water. The 800㎢ lake that resembled an ocean was boiling as if it was about to explode. Compared to this, the Devil Spring Mu Ssang had evaporated by using napalm and white phosphorous was nothing but child's play.

Magma contained high temperature and high pressure gas within. When liquid is transformed into gas, it causes an explosive increase in volume. The pressure from all that lava gushing out of the lake eventually triggered the volcano writhing to be unleashed.

Kaboom!

The volcano finally exploded. The powerful explosion completely obliterated the upper part of the crater. Tens of thousands of tons of lava and fragmented debris began exploding forth every second.

The humongous stone pillar supporting the underground dome's ceiling began quaking. Aftershocks rammed into it one wave after another. The ceiling at least 15,000 meters thick began rumbling and shaking.

The Bossaurus let out a dying scream. Though its hide was thick enough to withstand the boiling lake water, it could not endure the heat from the evaporation now shooting past 300℃. Various reptiles rampaged madly at this sudden onslaught of tribulations, but unfortunately for them, there was no escape.

Soon, the air of the Hollow World was filled with gases so toxic that humans could not possibly survive for one second.

Sorrowful cries of gigantic reptilian lifeforms, exploding lava, choking-white steam expanding at explosive rates, burning embers and ear-splitting roars of the volcano... A true hell on earth was created in this place.

There was no such thing as right or wrong in nature. Mother nature's indiscriminate rage utterly crushed all lifeforms living out their stubborn lives in this narrow underground territory. If its existence was known to the scientific world, the Hollow Earth would have caused a massive uproar, but just like that, it was disappearing for good.

But there was no point in lamenting or grieving over its destruction.

The universe is formed through atoms and molecules made up of atoms. These atoms and molecules uncaringly continue to cycle over and over again. Cosmic debris and dust flying around in outer space came together billions of years ago to create Earth, and the water delivered by various asteroids went on to decorate the newly-born planet.

All that blood from the gigantic reptiles gushing out like a fountain consisting of molecules of nitrogen, carbon, copper, and more that were used to make up the pteridophytes and bacteria found thriving on the surface.

The corpses of all the reptiles dying helplessly were nothing more than amalgamations of atoms and molecules that would cycle over and over again until it is repurposed as a body of homo sapiens born under the blue sky of Seoul in the distant future.

The true god was time. Time was capable of melting down any incredible incidents and any unprecedented calamities into obscurity, much like a cone of ice cream melting under the bright sunshine. Only atoms remained behind as records of what happened.

*

An Adras' body was indestructible, but it still had three fatal weaknesses: low temperature, viruses, and terrestrial magnetism. These three hurdles were the reason why Kamdoong could not immediately escape the Hollow Earth with Mu Ssang back then.

The temperatures of the Mesozoic Age's middle latitudes were between 60℃ to 80℃. Most of the animals avoided such high temperatures and thrived in the regions with high latitudes.

Some creatures still managed to carve out habitats for themselves in the middle latitudes, which ranged from 50° south latitude to 50° north latitude, by adapting to high temperatures in these regions. Kamdoong was certainly strong against high temperature, but its body structure was extremely frail against very low temperature.

Viruses were even more fatal. As a biologically-engineered creature, Kamdoong was a conceptless lifeform without a fixed form that possessed an ability to perform various levels of covalent bonding.

An atom consists of protons and neutrons forming a nucleus, along with electrons circling said nucleus. An atom is basically a small grain that requires tremendous energy to split apart, yet the distance between the nucleus in the middle and the electrons orbiting around it is considerably large.

If you enlarged an atom's nucleus to the size of a grape and viewed it, the electrons' orbit would be around 250 meters away from the now grape-sized nucleus. To put that in another perspective, even if you enlarged the atom to the diameter of 500 meters, the nucleus would remain as tiny as a single grape.

There is nothing in the space found inside that 250 meters. An atom is not a compact, tightly-packed grain, but an empty abyss similar to outer space. This meant that Gautama Buddha held a shockingly scientific worldview since he stipulated that all creations in existence were nothingness.

An atom does not exist on its own; it bonds chemically with others, sharing electrons in the process. Once the individual atoms' electron shells come in contact with each other, the electrons would start skirting around the two nuclei in a figure of eight. This is a molecule.

Tens of thousands of various atomic bonds, such as one's skin, blood vessels, hair, muscles, etc., that made up one's physical body, were built through covalent bonding. This bonding done by atoms maintains one's physical forms.

On the other hand, destroying that covalent bonding would turn an object back to atoms. The concept of 'extinguishment', which often pops up in fantasy novels, could be explained away as a type of covalent bonding destruction.

An Adras was capable of shortening or lengthening the orbit distance of the shared electrons between different atoms, thereby altering itself to any size and form it wanted. A human-sized Adras could greatly reduce its electrons' orbit to become a flea, or alternatively, transform into an elephant.

An Adras was meant to serve as a shell for a Concretus. With their physical transformation becoming ever more volatile and extreme, an ability to freely shape-shift was a crucial prerequisite for any Concretus if they wanted to 'migrate' into an Adras. This was the reason why Kamdoong transformed into a black panther the moment it acknowledged its concept.

Ironically, this superior ability was extremely vulnerable to viral attacks. If a virus invaded the gap between the relaxed atomic bonds, it would cause the nuclear force that make up its physical body to weaken. In human terms, it would be a case of viral infection — if the infection worsened, it would result in the nuclear force becoming weaker than gravity, causing the body to break down.

In animal terms... It would be death.

All the Adras that ended up in the Hollow Earth got wiped out precisely because the virus from the research subject factory had seeped into them. Viruses were also another reason why Concretus chose to implant the idea of non-concept in Adras.

However, Kamdoong had drunk Mu Ssang's blood, allowing it to withstand the viral attacks he had brought from the surface. Going up to the surface would mean Kamdoong would be exposed to the attacks of various viruses. If it wanted to escape from the Hollow Earth, it desperately had to strengthen its immune system.

The third and final hurdle, terrestrial magnetism, affected Kamdoong's 'collective intelligence'. While human minds functioned through the 1 billion brain synapses that connect to each other, Kamdoong exhibited its ability to think and reason through countless memory eukaryotes fusing together. Bees and ants had collective intelligence similar to Kamdoong.

A violent sunspot explosion would go on to cause the migrating birds to lose their sense of direction, while bees would fail to locate their hives. This was because the solar winds had shaken up the terrestrial magnetism. Such a trajectory would be quite similar for Kamdoong too.

Terrestrial magnetism – Earth's magnetic fields – was basically Kamdoong's GPS navigation data. If he could not accurately perceive Earth's magnetic fields, then it would be no different from an ant with its feelers removed. So, Kamdoong would have needed some time to acclimatize to the differences in the magnetic fields of 150 million years ago and those of the current era.

There was no such thing as an existence without weaknesses. Even the peerless-under-the-heavens Kamdoong was unable to overcome the weaknesses of low temperature, viruses and Earth's magnetic fields. So, one could say the creature was extremely unlucky in this case – just as it was nearly finished with its training to acclimatize and head to the surface, an earthly retribution from the gods had besieged it.

*

The lake's water, which was previously gleaming in a faint blue hue, had completely vanished and was replaced by a choking cloud of dense steam. But it was not just the lake alone; the entirety of the Hollow Earth was beset by the boiling steam and extremely toxic smoke.

The already-faint atmosphere was boiling. Inside this burning hell, where not an inch in front of your nose could be seen, was endless explosion noises and horrific screams.

The steam filling up the underground space soon broke through the condensation threshold.

A deluge of acid rain containing sulfur pummeled down. Raindrops, each of them thicker than bamboo shafts, pounded the boiling ground. This whole scene was reminiscent of a cauldron filled with boiling water being flipped upside down.

The weakened Bossaurus convulsed in its death throes. This creature managed to endure until the last moment through its tenacious vitality. Soon, though, its monstrous howls vanished. The volcano then demonstrated its power again.

A loud rumble sounded.

Like a reservoir with its dam bursting wide open, the volcano unleashed all the contents contained within its guts.

Fragmented debris flying out at the speed of sound mercilessly pounded Kamdoong's body. Even a piece of sticky lava came flying in, gluing itself on the creature's butt.

"Uht, that's hot! Bloody hell?!"

Kamdoong spat out the curse words that it picked up from its friend. Its tail transformed into a pair of tongs to pick off the lava piece and urgently discard it. Well-cooked smoke rose from its butt previously covered in lava.

Its fur, praised to no end by Mu Ssang himself, was now in a sorry state, visibly torn off and burnt in places. It was as if the creature suffered from the whitecomb, a sign that Kamdoong had been struck several times by now.

An object with constant mass would see its density increase when its volume shrank down; density was basically equivalent to toughness. If Kamdoong had remained a no-concept, shapeless existence until now, it could have shrunk its body size and withstood the external impacts.

After acquiring the 'concept' of panther, Kamdoong lost the ability associated with being a 'no-concept' being, only retaining the ability from when it was still a shapeless creature. In other words, it had lost the ability to reduce or expand the space between its molecules now.

The remaining ability was to either increase or decrease the density of its cells. This meant that it could only transform its outer appearance to a certain extent or get bigger or smaller, but that was about it – Kamdoong could not change the essence of its body anymore.

*

"Fuu~. Do I have to take my chance, then?" Kamdoong spat out a groan like a human might. The atmosphere filled with boiling gasses and steam easily reached the temperature of 300℃, but the creature did not suffer from any notable issues. Actually, its power of reasoning had become even livelier instead.

Kamdoong was a molecular lifeform. As such, it was unsurprisingly tough against high temperatures.

It rued all the time wasted on training to get acclimatized. The vertical tunnel its friend used to escape was a perfect place to carry out such training. Meanwhile, as much as thirty different viruses came tagging along with its friend. Such a large number of viruses proved to be a useful learning tool.

Kamdoong had finished getting ready to emerge into the outside world. It was planning to take its time to leisurely search for its friend, only for an earthquake to demolish the vertical tunnel.

Kamdoong glared at the tunnel, now gone without a trace, before turning around to leave.

Shuffle...

Kamdoong's figure melted into the void.

Shuffle...

Its figure reappeared in front of a massive metallic structure. It was a huge square stereobate one hundred meters in length and width, while another massive cylindrical structure fifty meters tall was placed above it. Some kind of a barrier seemed to be cast around the structure, as evidenced by all the fragmented volcanic matter flying in like bullets only to loudly bounce off an invisible layer.

"The Katomizer!"

Kamdoong glared at this machine. Here it was, the culmination of the Concretus' scientific achievement: a matter transfer device known as the teleporter. This machine was present at the research area when the planet's crust was overturned, causing it to fall into the underground space as well.

The Katomizer was developed during the Concretus' twilight years for the purpose of mass migration to another planet that boasted a similar environment to Earth. If 'warping' transported a matter to designated coordinates as is, then the Katomizer transformed matter into energy then transported it to the destination.

Although that was a far more advanced concept than warp itself, the device had a serious problem — it had not performed any concrete tests since its creation. Kamdoong did not mention this device when its friend was ready to travel back to the surface precisely because of its incomplete state.

The danger-response manual saved in Kamdoong's mind specified that the Katomizer was the only method available. However, even the slightest error during the process of transforming matter into energy and back would result in said matter scattering into the ether as tiny atoms.

"My issue is with the altered magnetic fields. I'm Kamdoong and you're the invincible Eastern Swordsman. Getting extinguished without being able to see my friend would be too much, you know..."

The Epidium it became friends with after bloody fisticuffs suddenly popped up in Kamdoong's mind. Even though that guy was nowhere near the physical abilities of an original Epidium, he was still just as violent.

Who knew that a muscles-for-brain Epidium could be that crafty? Epidiums originally did not possess that strange shockwave technique, for one. Just thinking back to those shockwaves attacking at the cellular level made Kamdoong shudder.

Despite getting pummeled to a near-death state, Kamdoong did not have any hard feelings. While Adras were designed for medical purposes, Epidiums were conceived to be combat types after all. Besides, 150 million years were just too long. Even an unruly Epidium was a welcome sight for Kamdoong.

The image of its friend, who unhesitantly offered his blood when an Epidium's antiviral blood was demanded of him, wavered in front of Kamdoong's eyes.

"It sure felt crappy while getting beaten up, but that's a small price to pay for making a friend, isn't that right! Besides all that, this better work!" Kamdoong grumbled while lightly jumping up to the top of the stereobate ten meters high.

This stereobate was not simply there to prop up the Katomizer. No, it was actually a nuclear fusion reactor meant to supply the necessary energy to the device.

Meandering any longer could lead to Kamdoong turning into a pancake courtesy of the tons of bedrock above. The creature's eyes began glowing white.

The data contained with the cylindrical structure floated up as a 3D image within the central processing unit. Outwardly, this structure seemed simple enough. In reality, though, it was a 4D system where millions of circles were overlapping.

Kamdoong's front limb extended, its claw scratching a section of the structure.

A crack could be heard. The surface on this section came off, revealing a needle hole. Kamdoong's claw slimmed down until it resembled an awl. The thin claw disappeared into the hole.

Accompanied by some rumbling, a smooth trapezoidal object protruded from the wall. Its length was around 80mm, and on its upper part was a hole with a diameter of 5mm, shaped like a lick of flame. Its design was the same as the 'Vajra' Mu Ssang had acquired earlier.

Kamdoong pushed its tail into this hole. The thick tail slimmed down enough to fit snugly into this small orifice. A fine needle emerged within the hole and collected Kamdoong's body fluid.