In the other room...

"What is this place?" Jurgen stared around him with awe.

As soon as they entered this place, the first this they saw are abundant amount magic crystals and metals popping out of the rocky floors and walls of this massive cave. This was the place behind those walls, the place that those molten knights and the emberman were guarding. Everytime they look left and right, they saw nothing but minerals and metals surrounding the area. The amount almost felt suffocating to look at, causing them to feel dizzy.

"So this was the things under the Mt. Vermont?" Jagger looked up and down, still couldn't believe of what he's seeing. "No wonder strong monsters are lurking around here, because this place has an abundant source of magic crystals." He added.

"Seems like it, this place looks enchanted though." Reynold uttered with a blissful expression after looking at the ember crystal he could possibly bring home.

"Well that's pretty much explainable since this place was never been explored by anyone before." Jurgen stated, hitting a large piece of crystal to check if It's really the real deal. The crystal sounded really hard and was pulsating with mana from the inside, convincing the stubborn old geezer that this was indeed a real ember crystal that's use for melting rune metals.

And speaking of rune metals, it seems like Edward stumbled upon a large chunk of it. It was popping out of the ground, dark-silver colored and has a smooth structure, almost looking like a crystal. "This looks pretty tough to mine." He said, attempting to pull the metal from the ground. After struggling a few seconds, he gave up and said, "It was indeed tough."

"Are this all valuable stones?" Bernard asked from the other side of the large cave. His voice was echoing and vibrating through the surrounding minerals.

"I think so." Reynold replied, gazing through the surrounding with his observant eyes.

And after a few minutes of sight seeing, they heard several loud banging sounds coming from the room where Grey and Ryner were located. This caused Edward to have an uncontrolled anxious face while staring back to the direction where the sound originated. Suddenly...

A strong pulse of mana wave reached their senses, sending shivers to their spine. It was a presence of a being they've never encounter before. And for everyone, this is just an unrecognizable power pulsating from the room where the emberman was located.

However, for Edward, this is something he already experienced before, back in the time when Grey first awakened in that forest. The nostalgic feeling of naturally potent mana, he knew it was him. And from then on, he already predicted what's going to happen and entrusted his faith into his son with a proud smile. "Let's head inside to check deeper, leave the fighting to them."

Meanwhile, inside that room...

Glaring coldly at the enemy with his fierce eyes, Grey could only hear his own heartbeat, pumping his veins with adrenaline. He stood firmly on his feet and brought up his hand to his ear level, fingers slightly bent while his arm muscles tensed uncontrollably. His head seems lighter and his senses have sharpened considerably upon releasing the huge amount of mana he storing in his mana pool.

"You're dead!" He menacingly grinned at the monster. Before making a slow grasping motion with vigor, commanding his mana to crush the enemy in his front. And soon, the suspended mana in the air moved on his will pushing the emberman from every direction, disabling it to move.

The lava monster seems struggling to move as its heavy body was lifted in the air by the mana being manipulated by Grey. It's molten body started to crack and the faint colored flames on its head vanished slowly along with the lava that was flowing down on its thick skin. The giant walking lava drowned in Grey's mana, hopelessly resisting its approaching end as pieces of rocks started crumbling from its body.

"What the... it's working." Ryner stared at Grey from a distance, after being saved by the kid just a moment ago. He could feel it... the overwhelming mana pushing the monster to the edge. It's hard to believe that it came from a kid. "This magic... this isn't telekinetic magic. The mana didn't transform to create repulsive and attractive energy... this is simply a regular mana, which means... this is an origin magic called 'Mana Arts'." Ryner quickly recognized the spell as it is a fundamental spell for any wizard of the royal military and he wasn't expecting a kid to be able to wield one.

He was amazed, but his amazement slowly turned to worry the moment he looked at the child's face. Grey was panting heavily, struggling to stand straight, and blood started dripping out of his nose. 'His body couldn't take it, he's losing it!' He rushed towards him, planning to stop the kid from exerting too much of his mana in the spell. But he was already late...

Grey was already halfway finishing the spell and with all the mana left on the atmosphere, Grey prepared to cast his finishing blow. By focusing all the spared mana in one single sharp point and aiming it at the monster's core located in its chest, he fired the remaining mana towards the emberman as he slowly drifted away from his consciousness.

"BOOM!"

The monster exploded upon losing its life. Large pieces of rocks were flying everywhere, causing semi-explosions on impact. One of this rocks flew towards Grey who's barely conscious after draining his mana pool and was unable to dodge it. But luckily, Ryner was there and used his excalibur to cut the pieces of rocks that were blown away by the explosion.

This narrative has been purloined without the author's approval. Report any appearances on Amazon.

"God... you can barely even walk." Ryner chuckled, looking at the man with a little hint of worry. He grabbed him by his back and lifted him up, carrying him all the way near the exit. "Our job is done here, let's leave everything to the adults inside." He uttered, his voice reached the child's ears but unable to reply at the moment.

The entire ceiling almost collapsed and the room was filled with smoking rocks of lava scattered by the explosion. The patch through the other side of the wall was also blocked by several rocks, giving them no way to follow Jurgen and the others. Leaving them no other choice, Ryner carried Grey and ran through the exit.

Ryner rushed hastily through the tunnel they've been before and reached the pitch dark part of the mining grounds. He was aimlessly running through the tunnel without seeing a damn thing and still managed to reach a dim lighted area that shouldn't be in that place.

"Huh?" Ryner looked ahead of him and saw a woman sitting on a rock with another woman lying on her lap while a torch was burning beside them. This caused him to blink a few times and took another glance before realizing that the person was Mira and the other one lying down was Rose. He finally reached the location, almost startling Mira.

"What are you doing in here?" Ryner asked with a puzzled expression. Sharply exhaling, he slowly brought down Grey on the ground.

Staring at his ripped clothing, Mira knew that his comrade fought on the edge against that lava monster. And after almost forgetting his question, she finally answered, "Look!" She pointed her finger not too far away towards the tunnel behind her.

Ryner followed her fingers with his eyes and was surprised to see large boulders, blocking their way to the exit. Much larger boulders and rock that he couldn't possibly break through.

Leaving them without any other choice but to stay longer in this hot place, Ryner asked once again, "Do you think it is them who caused this giant boulders to collapse?" His eyes were staring furiously at blank space.

"Perhaps they are." Mira replied, slightly leaning her head down, staring at the ground below. "Do you think we won't have any casualties?" She asked out of curiosity, gazing back at the unconscious Rose who's fully exposing her weakened body without any mana cloak. The pieces of anti-radiant material on her clothing are the only one sparing her life from all the heat, causing Mira to worry even more for her precious comrade.

Going back to her question, Ryner quickly answered, "We can't say that for now... but I hope to end this raid without anyone dying. And if someone die in here, I'll sure kill those fools." He fiercely spoke. He was also occasionally checking Grey who's also unconscious, exposing his body on the heat. This causes Ryner to worry more. Knowing that this kid was his stubborn master's grandson causes some anxious thoughts to play around his head.

"Agh!"

Feeling the pain on his chest after that rough battle, Ryner let out a grunt, as he sat down next to the lying Grey, his eyes staring upward as he breathed in an unstable rhythm. Soon, sweat started dripping down his forehead.

Upon hearing his loud pants, Mira quickly looked at him and gasped. "Huh... Aren't you breathing faster than usual?" She asked, worriedly staring at Ryner. "This also happens a lot recently during our raids this past few weeks. Are you okay?"

"Yeah... probably because... I spent most of my time training... that my body couldn't keep up." Ryner replied between pants, slowly closing his eyes and breathed in and out to stabilize his breathing pattern.

"I don't think that's it... Guildmaster was also worried about your current state of health." Mira bluntly uttered, letting out a long sigh.

"I'm fine... alright." Ryner replied with such a warm smile, wiping all the worry from Mira's face.

Mira only hoped that the man was telling the truth and let out another long sigh before leaning her body onto the cave walls and resting her back onto it.

Meanwhile, several meters away from them...

"Damn you Ryner, this is why I jate listening to ignorant brats!" Jurgen has been furiously grumbling for a minute until now. Looking around him, he still haven't spotted the boss monster that they came here for. And the old man couldn't help but blame the man that ordered them to come here.

"This is getting ridiculous..." Bernard whispered, almost chuckling, staring at a large piece of thick metal, attached to a wall.

They've been walking quite a ridiculous distance but still couldn't find the monster they're looking for. The only thing they've encounter is this 20 meters tall rectangular pieces of metal that looks exactly like a door attached to the cave walls. It looks thick and impenetrable, causing Jurgen to angrily stare at it.

"Let me guess, we have to break through this thing?" Jurgen annoyingly asked, hitting the giant door with the back of his finger. It sounded empty upon hitting it, which proved that this meat plate was indeed a door. After confirming it, the stubborn old man backed away a few feet from the door, exhaling loudly before raising his palm, facing the gigantic door. "Move away!" He ordered.

Upon assuring that everyone has cleared the way, he greatly focused his mana around his palm. Soon, a large compressed ball of wind was formed on his palm. Aiming for the gigantic door, he fired it at incredible speed, carrying a swooshing sound along with it.

At first, everyone was staring dumbfounded, not knowing what's about to happen since the wind spell seemed invisible until...

"BAM!"

A loud banging sound resonated in the air upon impact, causing everyone to jolt their body in shock. They all turned their heads towards the door where the sound originated and saw it unmoved by the spell that Jurgen casted. It seems like simple spell won't work against it.

"Let me try next." Jagger confidently insisted, moving a bit closer in front the door. He then, forcefully clenched his right fist before a red-colored mark on his right bicep was revealed in plain sight. His entire arm was soon covered with hardened rock before he vigorously punched the door.

"BAM!"

Another loud banging sound echoed throughout the large cave, causing everyone inside to cover their ears. After the sound occured, they went to check the door, but as expected, it didn't even wavered.

"Okay, I'm next." Edward also has a confident on his face when he walked near the door.

"BAM!"

But just like everyone, he also failed. And so, everyone inside that place alternately tried breaking the door, one after another. Some of them even tried casting combined attacks, but nothing happened, the door seemed unshaken by all the impact.

An hour have passed and the metal door remained intact on the wall. No spell worked against it. Everyone are exhausted and approaching the limit of their spirit marks. They've all given up on their knees, panting with one thought in mind, "This door is definitely indestructible."