The mana core. A mass of mana that is central to any human and most other living things that wished to use magic, which allows the owner of the core to store mana and to control it. James Lu's first encounter with such a core was not with his own core, but with that of his pet bear's.
In the darkness, a brilliant light appeared in front of him. James was able to detect the sphere of mana. He saw it, sensed the mana, and was able to roughly judge which way it was flowing. This was already a decently hard task in itself. The fact that James was able to do this without training could be considered natural talent. It wasn't like James hadn't been training - he had practiced detecting the monsters inside the dungeon. Part of it was probably due to the connection to said bear. Monsters, no matter how weak, knew some magic by instinct. But he hadn't really had any formal instruction. The person himself knew that his mana detection was already very good, and that he couldn't use magic because he was lacking in the ability to control mana. But he didn't know how imbalanced he was in the eyes of other people.
"Where am I?" he thought.
James couldn't really look around. He discovered that he couldn't move. However, he could feel a mass of mana .
"Is this my consciousness? I guess it's like that time where I received a reward from the dungeon, and I couldn't really tell what was going on. But this time, it isn't as uncomfortable."
However, his attention was soon diverted towards the things that were happening in front of him.
This mana presence was much bigger than skeletons or imps, although it wasn't at the size of that tier 4 monster. James didn't know anything about magic circuits, but he could tell that this core was unstable. It was a chaotic torrent of mana.
"This is...Leo's magic core. Aha."
Despite its instability, its size was really impressive. The mana in the core constructed a container that would contain even more magical power. However, the storage itself was empty.
James analyzed the magic core. If it was just him, he would've been clueless. However, he had a connection to Leo, who needed to instinctively understand the way gluttonous mutants' magic cores functioned. After all, if Leo didn't, then he wouldn't be able to survive. James combined this instinctive knowledge with his own to try and understand what was going on.
"There's no extra mana in the container. Plus, the actual container itself has flaws. Due to the volatile nature of mana, the container must counteract the decaying force. Mana follows the law of entropy, it seems, and wants to disperse. To sustain the container, it needs extra mana. Although, I don't know why exactly the extra mana helps. Eventually, the new mana starts to disperse as well, and the core needs even more magical power, leading to an infinite loop."
Even if his knowledge wasn't perfect, James roughly understood why gluttonous mutants needed to continuously consume things.
All of a sudden, a large influx of magical power caused the magic core to change. James, who was unable to move, simply watched as the core underwent a drastic transformation. He recognized it as the mana from the slime. James, captivated by the core, eagerly took in the sight.
After a period of time, the changes to the core stopped.
"Holy shit." James let out a small cry of surprise when he saw the reformed mana core. "It's beautiful."
A dazzling array, formed purely out of mana, appeared in front of James. It was perfectly shaped, made out of 4 identical structures in the shape of a tetrahedron, which he recognized as mana containers. However, traces smaller polyhedrons branched off of the large structure - they weren't there yet, but James, or maybe Leo, could tell that they were waiting to be activated. James had seen the intricate patterns and circuits somewhere before; in mathematical terms, its shape would be called a fractal, a pattern that repeated itself infinitely.
Mana would accumulate inside the containers. When they were full, the structure would create more and more containers, which would in turn store more mana.
In other words, this core could grow infinitely. At least, theoretically. There would be some issues in practical application, but the core would have to grow to a massive size for those to take effect.
James felt depressed. He could tell how amazing this mana core in front of him was, and it didn't belong to him, but to his pet Leo. James couldn't even control mana, so he felt left behind.
Later, James would learn that it was not him that was inferior, but rather that Leo was too out of the norm. To entities such as the beanie, gluttonous mutants were insanely rare and often incredibly powerful, making them potentially dangerous as well. Even more so, Leo, who had achieved this extremely early. In a sense, this was a result of James' hard work.
"Hmm?"
A trail of magical power extending from the core caught his attention. It led to another mass of mana in the distance. James couldn't exactly tell what it was.
As he was contemplating the magic core, James was interrupted. It appeared that his time in this place was up. When he returned to his senses, he was lying on the floor of the boss room, where he had been before.
"How was it?" the beanie asked.
James didn't respond immediately and laid on the floor for a few seconds.
"It was…slightly disorienting."
The transition to the space James had just been in back to the dungeon had messed with his head. It hadn't been as smooth as going in and out of the dungeon.
The beanie nodded to itself. It didn't know what James had gone through, as it had never experienced it itself, but it thought James would be able to gain something from the connection to Leo. It was right.
After letting the dizziness settle down, James sat up and walked over to the center of the room to collect everything.
"A tier 2 magic stone. This one looks more impressive than the others." James held it up to the light, as if he was an expert appraising his materials. He wasn't, and thus didn't gain anything from it.
James grabbed the throwing knife he had used to test the slime, then went over and picked up Leo.
Leo had changed. His appearance hadn't . However, its mana presence was much stronger. It was still hungry, probably because it had used up all its energy evolving. James was happy to feed.
"You haven't really changed at all." James smiled as he stroked Leo's head.
"Anyways, this is it." After having fed the bear and ushering it back into the dungeon card, James looked at the biggest reward for having cleared the 1st floor - the magic tome, which would allow James to learn magic.
The book was just as impressive as James had imagined it. James had been expecting to be disappointed, but he wasn't let down. It was a soothing shade of purple and had golden characters embroidered on the cover and spine. It seemed to pulse with power, drawing James towards it. Unfortunately, its shape reminded him of the chemistry textbook which had caused him much physical and emotional anguish.
"The magic tome that I've been waiting for. Or is it called a grimoire?"
The beanie answered his question: "A magic tome and a grimoire are often confused, because they are very similar. However, there is one key difference. This is a grimoire, not a magic tome."
"What is this key difference?"
"A grimoire has a will of its own. It doesn't have to be particularly intelligent, but it has to have a will."
"Woah." James looked at the book. "It's alive?"
"No, it's not alive, it has a will. Different things. Well, in this case, it's almost alive. Almost."
The beanie's answer didn't inspire confidence.
James grabbed the book and was about to open it when the beanie stopped him.
"This might take you a long time to digest. I suggest choosing a time where you will not be interrupted and can devote your full attention." Its tone was so confident that James didn't doubt him. Additionally, it also reminded James of something important that he had forgotten in his excitement:
"Oh shit! I forgot the reason why I got here in the first place! It was the damn music. My body's still probably on the floor. My parents were out though, I hope they didn't find my unconscious body. Otherwise, my mother would probably have a fit!"
James quickly stuffed the grimoire into his storage bag and collected everything he needed to.
"Sorry, bean bag! I'll talk to you tomorrow! Fuck!"
With a flash of light, he left the dungeon. The beanie had already seen James shout obscenities to leave the dungeon before, so it wasn't surprised by that.
"Bean bag?" The beanie was slightly affronted at the nick name. "I don't even know what that is."
James' equipment appeared on him whenever he hopped into the dungeon, so where was the beanie now that James wasn't in the dungeon? Who knows?
"What an interesting young lad," the beanie chuckled to itself. "He's just acquired the secrets to the pinnacle of human magic, and instead of studying it, he goes back because he's afraid of worrying his mother. He's a much more filial son than I ever was." A trace of wistfulness crept into the beanie's voice.
In a space beyond the reach of humans, a piece of knit fabric in the shape of a dome mused to itself, thinking about its past and the boy's present. They were the musings of a wise, old man who had lived long and experienced many things in his life.