Mercenary Black Mamba

Blacky patted Black Mamba's back with its paws as though they've been friends for a decade and disappeared into the dark. Black Mamba couldn't take his eyes off his friend's back for a long time.

He'd felt a sense of solidarity beyond their common origins. It could have been the synergy between the Concretus' slave, the Epidium, and the vessel of the soul, the Adras. Both of them were tools created by the Concretus, after all.

"Ha, I know humans with balls will become friends after a few punches, but I've become friends with a stranger. Anyway, how long do I need to climb up this thing!"

He sighed. The longest vertical cave in the world as of now was the Voronya Cave in Georgia. It was at least two kilometers long. A vertical cave was different from a cliff. Humans instinctively felt fear from darkness and concealed spaces. He had a fear of caves.

Fear and mental pressure exhausted his strength at a fast speed. Countless people lost their lives while exploring the Voronya Cave. When the count had exceeded 100, the authorities sealed the cave.

Black Mamba had a trauma of caves. He felt like he wasn't alive, even though he was, during the seven months he had spent trapped in the cave at Bang Tae San after Sai Dojiku had kidnapped him. He had to climb four to five kilometers up in the dark with a weight of 200 kilograms on his back. It wasn't an easy task, even for a Paranthropus. His chest felt stuffy. The dark tunnel felt like the entrance to hell.

There was another element of fear. An active volcano was rumbling three kilometers away. For now, it was steam explosions, but the cave could easily collapse once magma explosions occurred. With an earthquake, a portion of the cave ceiling could collapse.

Several tons of explosives had brought about earthquakes and exploded the Kaparja dam. He'd shoved a basket over his head by playing with fire. If the cave ceiling collapsed, he'd be Sun Wukong imprisoned underneath two celestial mountains. Well, his head was as hard as Sun Wukong's anyway.

Red lava trailed along the ceiling cracks and dripped down to the floor.

"Nimi jotto, if I get caught up in that, Epidium or not, I'm going to end up a skeleton."

Black Mamba looked up at the ceiling with tired eyes. It would be the end of him if the vertical cave was connected to a lava tube. He didn't want any lava pouring right above his head. He could only hope that the volcano wouldn't throw a temper tantrum.

Another problem was the passage of time. It wasn't a vertical cave he'd fallen into. 1,000,000,000 years was enough time to create something out of nothing. There was a possibility that a new layer of crust had formed over the cave. That situation would cause a mental breakdown. The problem now wasn't about how he was going to climb the cave but rather how he would face the unexpected situation.

"Well, something should happen!"

As always, his concerns didn't last long. A rice store worker, who later became the richest company owner in South Korea, always asked his subordinates, "Did you try?" It was reckless, but he admired a human's will expressed in that short phrase.

A heavy silence, which seemed to merge with the dark, filled the space.

Crack—

Splash—

Only the sound of his hand sinking into the wall rang. He dug out a section of the cliff with his left hand to create a left foothold before stretching up to hold onto the next section. At the same time, he stepped his left foot onto the foothold and pushed his body up so that the right side of his body went through the same movement. That was the alternating wall around wall technique.

The Paranthropus' strength, combined with the billion's water armor, created an impressive powerhouse. His hand dug into the wall, even with the slightest press. He didn't need to look for an overhang or a foothold. Obstacles were cleared with a single punch. Modern science couldn't create such a unique item. Black Mamba shrugged off those stray thoughts and concentrated on his climb.

"Seems like I passed the trial. I'm not fated to die so easily, huh."

200 meters ahead, the complexity of a sedimentary limestone cave remained. He sighed in relief. The main component of limestone was calcite. Calcite was soluble in acid rain or underground water. For water to be acidic, it had to be in contact with carbon dioxide in the air or organic acids accumulated from plant decomposition. It meant that the vertical cave was, in some way or another, connected to the surface. In any case, there was a way out.

Limestone caves were more complex than lava caves. Calcite that dissolved in the water created all kinds of shapes, such as stone pillars, stalagmites, curtains, and shields. To Black Mamba, who was climbing vertically, it was a foothold and an obstacle.

Even the solid rocks that were embedded became obstacles. If it hung over his head like an umbrella, he had to break it or climb around it. He had no choice but to regularly use his resonance waves to avoid such obstacles in the dark. Like a bat, he could identify any obstacles with ultrasonic waves.

As he climbed up 500 meters, the faint light emanating from the bottom of the volcano with its every heave disappeared. Night vision and the inner eye was useless in absolute darkness. There had to be at least some light to raise the capacity of his night vision, and his inner eye could only activate once it detected a certain object. If he couldn't see, his inner eye had nothing to zoom in on.

Crack—

He shattered a flat rock shield hanging over his head. Obstacles continuously appeared, despite it being a vertical cave. The sound of rocks falling toward the distant Jurassic world was like a wailing ghost. He could turn into one of those rocks if he slipped. Cold sweat ran down his back.

"Ugh, there's no end to this. I need to take a break."

It wasn't easy climbing a vertical cave without any equipment in the first place. His arms ached three kilometers through the climb. He still had strength, but his hunger and thirst caused problems. His stomach screamed for food, and his muscles trembled as it lacked energy.

He supported his entire weight with one hand and began to dig into the cave's wall. Using up all of his strength, he dug out rocks the size of his head. The billion's water armor acted like an undefeatable ally. If he didn't have it, he would have been wiped out while trying to dig into the rocky wall with his resonance waves.

He roughly dug out a resting place and shoved his butt in. He rested for two hours. He unpacked the lunch that he was carrying on his back. The moment he released the Gorgon around its neck, the seal-like creature screeched. Water creatures seemed to be more persistent than land creatures, seeing how it had survived a cracked skull.

"Namu Amita Bul, may you be reborn on land in your next life."

Still, he didn't forget to pray. He ripped the creature's artery with his fingernails and drank its blood. He'd brought it all the way here alive just to drink its blood. There was no water bottle or water. He had no choice but to drink its blood.

He split its belly and pulled out its liver and heart before chewing on it. The liver was prone to spoil quickly, but it was absorbed quickly into the body. It was also rich in nutrients. Of course, that was according to a mammal's terms. Poison also accumulated in the liver. There was also poison in the bodies of water creatures. His tongue became numb, but he didn't care. His body wouldn't be affected by the poisons of living things. The all-poison resistant body featured in martial arts novels was him, the Paranthropus.

"Hehe, I'm the real monster here, not this b*stard."

Laughter escaped from him. He tore apart raw flesh with his teeth in the absolute darkness. Blood was dripping all over his mouth, and his eyes gleamed in blue. It wasn't the appearance of a human.

One of the seal-like creature's hind legs disappeared in the blink of an eye. It tasted horrible, but he had to save as much food as possible. The dinosaur's meat was thick and tasteless, but it was several times better than rotten worms, scorpions, and insects. He tied the remaining meat with the Boss-saurus' tendons and slung it over his back.

"The air changed."

His sensitive sense of smell and touch detected the change in air density. Sulfur and ammonia had decreased while carbon dioxide had increased. It meant that there was another space nearby. He pushed his strength further and climbed quickly.

A large vertical cave was often created by several uvala sinking together. It meant that there was an entrance on the surface. Of course, a horizontal cave would appear if he ran out of luck. That would only happen if a large-scale tectonic plate movement occurred after blacky fell into the underground world.

He didn't know how many changes had occured over the years. If a new crust had covered the vertical cave, it meant that what he had detected wasn't the surface but a horizontal cave. There wouldn't be any other misfortune.

He activated his resonance waves to determine an accurate location. There was a strange airflow 500 meters opposite him. His heart raced. He was finally getting out of the land. He'd climbed up more than five kilometers. Aside from his strength, it wasn't something that a human mind could handle. He could only hope that the exit was connected to the surface.

"What?"

Black Mamba paused amid his climb using the alternating wall around wall. There was a light in the darkness. It was weaker than an oil lamp but stronger than a firefly. Was it a sea sparkle? He grew curious. He had to go around the other side to check. He had to travel a distance of 100 meters around the vertical cave of 30 meters in diameter. 100 meters was a daunting distance for his body that was beyond exhausted.

His worries didn't last long. He changed direction and headed toward the light. He missed the light too much to give it up. He could activate his night vision as long as there was a little bit of light in the cave.

The closer he got to the light, the more it shone like a mirror. The cave got steeper. That wasn't normal. Why did the limestone cave change so suddenly?

Moreover, the billion's water armor slid slowly off the back of his hands. It looked like a snake peeling off its skin. He wouldn't have noticed if not for the faint light, which activated his night vision.

"Ugh, it's humiliating, but what else can be done?"

He opened the front of his pants and held it out. He was just about desperate to relieve himself anyway. Urine consisted of 95 percent water. Now wasn't the time to debate things. He didn't have the confidence to climb the steep wall without the billion's water armor. The powerful stream soaked both of his hands and disappeared far below. The billion's water armor, which was peeling off his hands like a snakeskin, penetrated back in.

"Huh? What is this?"

It wasn't a colony of sea sparkles, but rather something solid stuck on the wall. He dug around it with the billion's water armor and pulled out the shiny object. It was metal in the shape of a cucumber cut vertically. He cleaned the surface with his hands equipped with the billion's water armor. The rocks stuck to the metal fell off.

The light got brighter once the rocks fell off. He grasped it tightly with the billion's water armor and twisted it. Despite a power strong enough to bend steel, it didn't budge. Black Mamba didn't think long about it.

"There's nothing more like an everlasting battery. I'm going to use you well."

Black Mamba placed the strange metal in his mouth and climbed up the wall using alternating wall around wall. How fortunate was it that he could distinguish objects even in the dark?

"Nimi Jotto!"

A shout echoed around the cave. It had taken him five hours to climb up, only to be greeted by a horizontal cave. He'd been hoping the whole time, but God hadn't listened to his sincere prayers. It was a completely different place from where he'd been swept away by the currents. It was hard to estimate the depth. Strength drained out of him at the thought of searching through another cave.

Black Mamba had the wrong idea all along. The vertical cave he had climbed out of wasn't an uvala terrain but a meteor crater. If a large meteorite fell on limestone terrains, the immense impact would create a crack right along the crater's sphere.

The split limestone then changed according to the heat and pressure generated during impact. The bedrock created in such a manner was the breccia. The breccia would turn into a waterway, melting the limestone with its water. Several years later, a vertical cave was formed.

Cenotes, which were commonly found in South America, turned into vertical caves in such a manner. Cenotes were an underground pool where water from above seeped through the limestone layers.

When a part of the Eurasian Plate of the Mesozoic Era was lifted as a fold, an anticline occurred in West Asia. The existing bedrock ended up splitting because of the pressure of the plate, which was 2,000,000 square kilometers wide. That was the reason why the lower part of the valley's cave opened up into the underground world. Due to the large-scale tectonic plate movements at the time, the Concretus civilization disappeared from the surface without a trace.

There was no way that a vertical cave was connected to the surface in the first place. Black Mamba suffered the misfortune of having to pierce the center of West Asia's plate by crawling underneath it. The terrain created by the breccia brought great wealth to Assad but tormented Black Mamba. When there is this, there is that, and that occurred because of this.

"Ugh, something should happen."

He collapsed onto the cave's floor. How fortunate that a human could lie down? He'd climbed up almost 6,000 meters and not 4,500 meters. His limbs ached, and his head buzzed. He twisted into the lotus position and maintained his inner peace.

He stared at the seal-like creature. Six years ago, he'd survived two weeks on a single rat snake. As long as it didn't decompose, he could last a month.

"Come on, Dong-bang-bull-pae. You have food, and you have air. The blue sky awaits you."

He slapped his cheeks and started digging into the Boss-saurus' belly. Black Mamba began his march of isolation in the dark after filling his stomach. At least, the glowing rock he had gained out of pure luck became of great help.

The cave continued endlessly. When he passed a hole the size of a dog hole, an area the size of a football field appeared. When an underwater cave appeared, he dived and climbed up a flowing waterfall. Several times, he forcefully widened the small passages and climbed through it. Despite his immense power, Black Mamba started feeling tired.

He'd earned it. He cursed himself for exploding all the missiles in Berkut.

"F****** b*stard, you blew off those missiles without a single thought, which is why you're suffering now."

"Damn f***er, how was I supposed to know? I'm not Jang Shin."

"30 would have been enough to blow the whole place apart."

"Ugh, dude, what am I supposed to do about it now?"

"You crazy b*stard. Why didn't you do things in moderation? Was someone about to capture you?"

"Shut up, idiot. I need to earn my money, right?"

He endlessly mumbled, walked, ran, crawled, and swam. A rare scenery appeared before him sometimes due to the faint light, but he didn't spare a glance. He was not a tourist but an escapee with his life on the line.

Black Mamba's senses were special. He could sense the change in air pressure and density. His sensitive senses worked as a guide every time the cave split into different passages.

The cave went up and down, but he was approaching the surface. He could tell just by the difference in temperature. The hot air had changed, enough for him to feel the cold. That meant the surface wasn't far.