***Archimedes’ POV***

The dungeon was noticeably changing. The soil in the walls was no longer a uniform brown color: there were streaks of red, grey, black, and even yellow. Along with the changing mineral contents, an earthy smell was released into the air. Dozens, hundreds, thousands of strains of bacteria were released into the element-rich soil, and dozens of strains of fungi were released just after them.

It could be explained in a few words, but the actual process took a great deal of time and concentration. The list in the corner of his vision was expanding rapidly, but he just did his best to ignore it.

Archimedes moved on to microorganisms, dropping hundreds of species, then he moved up one step to insects and worms. He squeezed his memory for every useful compound he could think of, and then he saw a rather familiar message.

Congratulations! Dungeon core Archimedes has registered a new Material! New Material registered: Vivacious Soil.

Except that it wasn’t new. Archimedes could understand that puzzles identical to his had never been created before, but he himself had made this soil in his previous life.

“What the hell do you mean ‘new Material’? I created Vivacious Soil more than six thousand years ago!”

The voice of the world did not answer questions, but it was also something that didn't comment on the situation, until recently. Weakly, as if battered by his accusations, a faint window fazed into view.

This is the first time Vivacious Soil has been made in this world.

The first time in the world, it said? The first time in this world… in this world.

Of course. He should have suspected it from the time he encountered that long ear boy.

“So this world is not the same one I lived in before... What is this world called? What was my previous world called?”

Before, it was Rachon. This is Usain.

Usain… Archimedes meditated on the word for a moment, then thought sternly. “Then, why did you send me here?”

Archimedes waited, but no more windows appeared. There was some window-like thing that tried to appear, like patches of ink spreading through water, but it wasn’t able to fully materialize before sputtering out of existence. Archimedes sighed and put the matter aside. He had more time-sensitive work to do anyway.

***Anther’s POV***

After failing to solve the sliding puzzle multiple times in a row, Anther realized that he no longer remembered which combinations he had already tried. He might have kept trying if he thought he would get lucky, but this puzzle was too unforgiving for him to hold on to that kind of hope. Sighing in frustration, the boy turned around and trotted back down the mountain. There were no more detours after that, so it wasn’t long before he was back in the village. From the main road, he ran past his mother’s house, past his father’s house, and on a bit more, down some winding trails, until he found his great aunt’s house.

“Aunt Januiil,” the boy called, throwing aside the curtain hanging in the doorway and letting himself in.

“Hold on! Just a minute!” A woman’s voice came from higher in the tree, along with a sudden thump.

“Aunt Januiil?” Feeling concerned, Anther hurried to the ladder and started climbing. His great aunt’s house was already three stories tall; he estimated she would be on the top floor. Indeed, after climbing as high as the ladder would take him, Anther caught sight of a woman muttering while scooping dried flowers back into a clay pot that had fallen from a shelf. It was a wonder the pot hadn’t broken against the floor, but it looked to be coated with something clear to prevent just that.

Januiil spared an instant to glance at her great-nephew, then looked back at her hands. “I’m fine, I’m fine. You startled me, child.”

Contrary to what one might think when imagining someone’s three-hundred-year-old great aunt, Januiil didn’t look any older than a human woman in her late fifties. She had some wrinkles, sure, most notably crows’ feet, but she seemed quite put together. What would stand out more than her wrinkles would be her hair. It reached all the way down to her mid-thighs, where it was loosely tied in a knot near the bottom. It seemed to have faded from a rich mocha to a pale tawny.

“Sorry, aunt Januiil,” Anther apologized. He would have helped her clean up, but she had finished already. The old elf dropped the pot’s lid back in place and put it back up on the shelf.

“It’s no problem,” she dismissed, clapping her hands to dust them off. “Did you need something, Anther?”

“Oh yeah!” As if he’d only just remembered why he’d come, the boy’s eyes lit up. He quickly shrugged off his bag and pulled out the herbs he’d gathered. It was a fibrous white plant, so strange looking that one might think it to be a fungus at a glance. He’d only gathered a few handfuls of the stuff, but that was more than enough to make use of.

“I went out and... gathered some more dust vines. Can you make me more medicine?”

“Well, of course I can,” she said, taking the plants from the boy and examining them with shrewd eyes. “Are you still having problems?”

“It was worse... yesterday, I think. But people said I was stalling a lot.”

Januiil rubbed her eyes and let out a breath. “Well, you’re doing it now. I wonder if I should make something stronger.”

Anther tilted his head, “Won’t it work out if I just take more?”

The old elf rolled her eyes and flicked the boy on the forehead. “This boy. Listen, you can’t just take more medicine. Even the best herbalists can’t help but leave behind a few toxins no matter what medicine they’re making. If you take more medicine, you’re also consuming more toxins. You’ll get sick if you keep that up. That’s the whole reason we develop stronger cures: the less medicine people have to take, the healthier they’ll be.”

Anther frowned and rubbed his forehead, ignoring his eyes which had become moist on their own. “But, aunt Januiil, won’t I have to take medicine for the rest of my life?”

She glanced down at him and rolled the dust vines in her hand. After chewing her cheek for a moment, she nodded. “That’s right. So you should tell me quickly if the medicine I make for you isn’t strong enough. Now go wait downstairs while I throw something together.”

Januiil watched as her great-nephew picked up his sack and scurried down the ladder, then called after him, “And don’t be afraid to sweep the rugs while you’re down there!”

She snorted and looked at the dust vines, then to her jar-stocked shelves. “Mana-focusing potion, huh? Do I have any Crue eggs left? And where did I put my glass stirring stick?”

Anther tidied up a little while he was waiting. Not only did he sweep, he even took the rugs outside to beat the dust out of them properly. It was about half an hour before his great aunt came down the ladder with a small clay jar in one hand.

“There you go,” she said, curling his fingers around it and patting the back of his hand. “You take one, every other night, alright? If there are any problems, come straight here, you understand? Little problems too. New medicines can be dangerous the first time you take them, so don’t write it off, even if it’s just a little stomach ache.”

“Thank you, aunt Januiil!” the boy gave a brilliant smile, and the old woman wondered if he’d really been listening.

“As long as you understand,” she said, frowning and rubbing the back of her neck.

The next morning, instead of taking his usual medicine, Anther opened the new bottle. Inside were seven indigo spheres, about the size of the nail on his pinky finger. The boy tossed one into his mouth and swallowed it, then put the bottle away carefully. He quickly did all the chores his mother asked him to do, but when he tried to run off after that, she called out.

“Anther, sweetheart, if you’re not doing anything, you should go check on your father.”

The boy stopped his enthusiastic feet and realized he had been too hasty. “Yes, mother.”

***Archimedes’ POV***

The contents of the soil and the air had been balanced. He had added more water and enhanced it. All the little bugs and grubs that needed to be present had been crafted and set loose. A few small mammals had been strewn about to eat said bugs and the various plants that were growing. As long as some force existed to periodically cull these small mammals, a balanced ecosystem would have finally been created.

Congratulations! Dungeon core Archimedes has registered new Materials! New Materials registered: Fresh Air, Life-giving Water. Congratulations! Dungeon core Archimedes has registered a new Biome! New Biome registered: Fertile Cave.

“Yes, good. Now please compress all of that as much as possible. No, just compress the whole thing again: it’s still too long. Get rid of all the boring stuff.”

Materials were already obvious, but Biomes, well, they weren’t creation models per se. One couldn’t select a Biome from the list and instantly slap together a functioning area. Archimedes figured they were only listed so that a dungeon could check what it had done to create the Biome in the first place in order to recreate it later. In the case of his Fertile Cave Biome, it had come about as a result of his higher-tier air, water, and soil Materials, as well as the various plants, bugs, worms, and small mammals he had put together in one region. The name described it well: it was a place where things would grow easily and reproduce frequently.

Creatures in a dungeon could survive off of nothing but mana, but that would leave less ambient mana to repair damages and reset traps and puzzles. If the ecosystem was balanced well enough, dungeon creatures would reproduce while consuming almost no ambient mana. In the Fertile Cave Biome, for the virtue of it being a named Biome, things would reproduce even faster than usual, at no extra cost.

This was the basis for the brutal cheat Archimedes had discovered in his last life. It was useful to him then, even though he was already a dungeon of over one-hundred floors. It would be invaluable to him in his current state.

Aside from possessing a Fertile Cave Biome, one other thing was necessary to use the cheat, but it was an innate ability that every dungeon core possessed on awakening: Destroy Creation.

Archimedes had had no use for it so far in this life, but the effect of Destroy Creation was to disassemble a dungeon structure or creature and reclaim its mana cost. The cheat lay here: it didn’t have to be one of Archimedes’ handmade creations for him to use Destroy Creation on it. Just so long as it was a creation of the dungeon, he could reclaim its default mana cost.

All the rabbits and voles and shrews that were multiplying in his Fertile Cave, costing him no mana to produce, could be destroyed and turned into mana. It was astonishing to the point that it seemed as though mana was being drawn from thin air. Of course, it wasn’t really coming from nowhere. Ether was consumed and turned into mana to create every naturally born creature. No matter how people spoke of it as a resource, ether wasn’t something that could be depleted or needed to recharge over time. Ether wasn’t tied to time at all: it existed on a cause and effect basis, flowing out, as needed, from the mysterious ethereal void.

Archimedes could produce mana ad infinitum because his crystalline body was a portal to the ethereal void.

Well, all of these were interesting things that Archimedes had learned over his long life, but the important thing to take away was that he now had free mana potions on auto-spawn. He could now focus on his expansion in earnest.

**Anther’s POV***

Anther’s face turned slightly red as he struggled to carry a large jug of water. Walking beside him, though with far more ease, was a man that resembled the boy a lot. Anther’s father, Yinether, looked a lot like an older version of his son, except with longer, darker hair, and sleepier eyes.

After coming all the way from the river, they finally set the jugs down inside Yinether’s house. Anther’s father gave him a pat on the back. “Are you alright, Anther?” he asked with a warm smile.

The boy dragged his sleeve over his forehead to wipe away the sweat. “I’m fine,” he said, his eyes lighting up again. “Is there anything else, father?”

Yinether loosely folded his arms and stared at the ceiling. “Hm. We took care of the weeding and the dusting, and we got water. I have a little tree-trimming to do, but you’re still a little young to help with that.” The elf looked down at his son and smiled. “No, that’s everything. You can go play now.”

The boy grinned and hopped happily. “Thank you, father, I’ll see you later,” he yelled while sprinting outside. His father could only shake his head and laugh at being abandoned so easily.

Anther tried to move his feet quickly, hoping he was still in time, but when he dropped by both of his friends’ houses, he found out it wasn’t so.

“Sorry, Anther. Kasser already left to hunt just a little while ago.”

“Oh dear, I’m sorry, but Myla ran off somewhere after finishing her chores.”

That’s why it was no good to be the last one to finish your chores! Sure, he did the same thing more often than not, running off to play on his own, but at times like this, it was irritating!

Those loners, he muttered internally, kicking a tuft of grass.

Well, he’d already gone alone twice, so there was no difference if he went alone a third time. Anther went home, grabbed his bag, his bow and quiver, and something extra before running back to the dungeon.

***Archimedes’ POV***

Archimedes had been expanding non-stop since he completed his first Biome. About twelve hours had passed since then, and by harvesting “mana potions” whenever his supplies were low, he had already completed another hallway.

The thing about Biomes was unless he did something to stop it, it would spread to cover the entirety of whatever floor it was on. As it did so, the amount of ether and “mana potions” present to process into mana only increased. Archimedes was accumulating 124 mana per hour even without making full use of his brutal cheat.

He still used it, of course, maliciously. Efficiency was a dungeon core’s instinctual desire, and there were few things more efficient than this. It felt good to follow his basic instincts. And besides, to Archimedes, the creatures of the dungeon were just byproducts of his body. Unless they were particularly strong or useful, he didn’t feel any pain at their sacrifice.

Before Archimedes could focus on carving out his third room, he was interrupted.

So he’s back again.

Indeed, the long ear boy had returned, alone, again. For the life of him, Archimedes couldn’t understand why that child was always alone.

This boy wouldn’t be the only sapient thing in the area, right? There are other intelligent creatures on this planet, right?

Archimedes was about to go back to work, but this time, before working on the puzzle, the long ear boy grinned and pulled something out of his bag. It was a small notebook. So he was finally taking the first puzzle seriously, was he? Archimedes felt a rising sense of approval, even though he should have been against his puzzles being solved this early. Well, it would get boring if nobody could solve the puzzles at all. Although it helped the boy keep from repeating the same mistakes, he still wasn’t able to solve the puzzle after many attempts.

It wasn’t long before the boy left, and Archimedes was left to his work, and, if anything, he felt even more rushed than before. He now had evidence that the long ear boy could leave his dungeon and come back in just a single day. On top of that, his first puzzle was being systematically dissected. It would be good if he could quickly put up his fourth puzzle before the first was broken.

______________

Costs (Compressed):

Spoiler: Spoiler

Monsters (per 1)

Dungeon Bat: 130 / 7 min | Wolfbat: 30 / 5 min

Animals (per 1)

(Omitted)

Plants (per 1 or per 1 square meter as appropriate)

(Omitted)

Fungi (per 1 or per 1 square meter as appropriate)

(Omitted)

Materials (per 10cm x 1meter x 1meter / real-time)

Fresh Air: 23 | Live-Giving Water: 41 | Vivacious Soil: 34 | (Lesser Materials Omitted)

Constructs (per 1 / real-time)

(Omitted)

Puzzles

(Omitted)

Biomes

Fertile Cave