The human lady was back, and she was hostile. I watched in horror as she effortlessly cut down my modified rats, her sword glowing with red soul essence that burned every rat she cleaved in two. It was a slaughter, and by the time she was done burnt rat corpses and black blood littered the floor.

Rage filled me and I was tempted to lash out, to strike her down right this instant but I refrained. There was no telling what she would do if she found out that the cave itself was the dungeon, this was a lesson, one that I would remember and pay her back for when I got the chance.

“Blasts! Where is the bloody dungeon core!?” She shouted as she cleaned and sheathed her blade.

It was evident that she was puzzled by my peculiar nature, the lack of a physical dungeon core had thrown her off, and it amused me greatly. Though she killed my rats, I didn’t lose much, their fragmented souls floated within my walls, surrounded by a shield of soul essence that kept them safe.

I was going to remake them once she was gone, stronger and better too.

I watched as the human lady, likely an adventurer, meticulously pick apart my cave, searching every nook and cranky that she could poke the end of her strange metal box in. In the end though, she gave up, frustration and anger written on her face as she left.

When I was certain that she left, I respawned two modified rats, one male, and one female, and tested out my matter-shaping capabilities by shifting the stone around them to create a hollowed-out space large enough to fit them and their kids many times over and partially sealed it off. I modified the two rats so that they would never need light but stopped halfway as I realized I only needed one female rat.

I despawned the male one and modified the female rat to reproduce periodically, limiting her to 20 rats. Once that was done, I absorbed the dead rats and blood before allowing the spawning rat to begin reproducing and within 20 short minutes the cave was filled with 16 rats once more.

She would be the sole respawner of this floor, it was a cruel fate but I made sure she was happy, it was her duty now and she took pleasure in doing so.The modified rats before weren’t going to cut it, it's quite evident to me now that humans possessed supernatural powers in this world, or at least some of them.

They knew about dungeons too and had a way to find them, it was only logical to assume that they had a way to use them if they spent so much time and effort looking for them. One could only imagine what they’d do with me, an oddball among dungeon kind.

I needed creatures that could defend me, and as it were now, I had no creature capable of doing that adequately and I was about to change that. The modified rats clearly weren’t going to cut it, seeing as how they were easily cut down by that lady adventurer.

I selected a random rat and willed it to grow to twenty inches, changed back their color back to black, and elongated their claws and willed them to be as sharp as possible.

I made their muscles powerful and gave them the ability to explode with a sudden burst of strength as a last-ditch effort, when that was done, I moved on to their mouth, elongating their fangs and sharpening them as well as giving them the ability to spread their mouth unnaturally wide.

Lastly, I thickened their fur and made their tail whiplike and elastic, then I slotted in their souls and made some changes to the spawner rat to reflect the changes I made. Finally, I copied the changes and pasted them on the next 19 rats, watching them take effect almost instantly.

I retracted my presence and admired my work, truly nightmarish creatures. They still had rat-like features such as whiskers and an elongated nose but otherwise they looked like a completely new species.

They ate up a good chunk of my soul essence, but I felt like it was worth it, only time would truly tell though.

I noticed that even though they got a lot bigger the draw on soul essence to feed them was still negligible, even more so than before now that there were only twenty of them. I still had thirty souls left though and didn’t want to make more rats, so I decided to make a new room.

I shifted my attention from the soul essence network and to the walls at the back of my cave and began working on it.

I deleted it? No, it would be more accurate to say I ate away chunks of it. I felt like I was eating stone, but it had no distinct flavor. The process was slow at first, but I pushed a bit more soul essence into it along with my will and the stone rapidly melted away. Information about its makeup and chemistry flowed into me but it didn’t remind me of any type of stone I was familiar with, it was probably one that was native to this world.

Anyway!

Soon, I had a nice and perfectly circular tunnel. Next, I repeated the process but aimed it downwards this time. It was even faster now that I had a bit more experience and I finished in just five minutes.

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I carved some steps into the walls of the tunnel in a spiral pattern until they reached the bottom where I started another horizontal tunnel the same length as the first one. Next, I began carving out my second floor. This would be my first proper floor, the cave was awesome and all, but it was just a naturally formed cave and while I could've shaped it into what I wanted I decided not to, at least not for now.

I wanted this floor to be as big as possible, I still didn’t know what theme it would be, but I had a few ideas. Ideally, a forest or jungle-themed floor would be nice, but I had nothing related to any of those and I only had the pattern for two creatures so far, not a great start but I planned to fix that very soon.

I wanted to make a proper dungeon since I had no reason to fear getting destroyed. Until something showed up that was a genuine threat to me, I had no reason to fear invading creatures, I had no core that could be destroyed or enslaved.

The only limiting factors were soul essence and the lack of patterns, because while I received a decent amount of soul essence every second it barely was enough to work without bottoming out a few minutes in. I was careful not to dip into absolute zero territory, but it was still annoying.

Because of this, I returned to the first floor and stretched it a bit while maintaining the natural cave look and added ten more rats. I was a bit tired of calling them rats though, as they weren’t that anymore. In the end, I decided to call them ratlings, since they weren’t that far off from becoming human-sized, well, human size was a bit much. Kid-sized was a better-fitting term.

Without even telling them to, they began to use their powerful muscles and tails to stand on their hind legs, they even began learning to run on them too, which was interesting. Their fragmented souls also grew a bit and pulsed brighter.

What was this?

The discovery was an amazing one, as it meant that my creatures could grow, organically too! That was great, it meant that I could create entire ecosystems that functioned on their own, with little to no input from my side.

The prospect was tantalizing, and I was practically itching to try it out but then I made another notable discovery; the souls of the ratlings gave more soul essence.

This was another welcomed discovery, did this mean that larger and more powerful souls gave more soul essence? I could see the logic in that, but I wanted to test it out, just to be sure. I had no way of artificially growing a soul, though, it just happened the longer the rat lived and the more things it experienced.

This was all so fascinating to me, especially the mechanics of the soul, which I’m sure I barely touched upon. Still, even though the discovery was a wonderful one, I had no viable way to apply that knowledge. The ratlings needed to experience new things for the soul to grow the most.

I realized that it grew regardless of that as the ratling aged but the thing that made it grow the most was new things, and within an hour or so any newly spawned rat’s soul would stop growing and would mostly stagnate.

Eventually, every ratling on the first floor reached this state and their souls stopped growing. Their souls were large enough to be split again, which I did, bringing my total number of souls up to 130. The upgraded souls constantly provided me with a bit more soul essence, which I used to start floor two.

It was barely enough but it would have to do.

I shaped out a perfectly cubed room and waited for my soul essence to regenerate, then elongated it. I repeated this a few times until I had a perfectly cubed room the size of a house. I then shifted my awareness to the entrance to this room and found it severely lacking.

It was just a perfectly circular hole big enough to fit a party of four fully grown adults connected to a spiral staircase. That was it, which was unacceptable, I wanted my dungeon to be something else, unique and impossible to erase from memory.

I decided to change that, first was light. As my dungeon was now, it was dark, like really dark. Though I could see without problems I’m sure no invading creature possessed this skill, so I had to make something for them.

On the ceiling of the tunnel, I willed an ethereal tendril of soul essence to extend downwards, I then shaped it into a perfect circle and tried to will them to solidify and produce light. To my surprise, it worked, and a ghostly but beautiful glass-like crystal formed and hovered at the absolute center of the ceiling.

The pattern appeared inside my mind, and I replicated it, placing one at the top of the staircase. Next, I tried controlling the light and it worked with surprising ease, I found out that I could control exactly where the light it was producing stopped and much more.

I limited the light being produced by the soul lantern, as I was now calling them, to extend to the edge of the tunnel connecting to my second room. I did the same for the soul lantern in the staircase leading down as well, the light they produced was powerful and bright, so bright that I had to dim the one in the staircase as it was lighting up my first room.

I was tempted to place a soul lantern on the first floor as well but decided against the idea. My Ratlings were already adapted to the darkness of the cave, and while it would bump up the size of their souls a bit the soul lantern would go against the theme of the floor.

Next, hollowed out both edges of the tunnel leading to the staircase and formed a perfectly circular slab of stone, and slotted them into the hollowed parts of the tunnel. These would act as doors and block any light from reaching the first floor.

Now came the interesting part, I willed some soul essence into the circular slabs and sent my thoughts over to it. I wanted the first door to only open when the first floor was cleared, and the second only when they were in the tunnel leading to my second floor. The soul essence didn’t stick and returned to me every time, so I decided to try something else.

I hollowed out enough space for them to roll back into and felt something shift.

With an ethereal snap, the soul essence fused with the stone doors, and I could feel the command floating there.

Okay, in hindsight that should've been obvious, where were they going to go? Turns out fantasy had logic too, who would’ve thought? I still didn’t know if the command would work exactly how I wanted it to but only time would tell.

I still didn’t have a second floor to show but it was good to prepare. I repeated the same thing for the tunnel leading to my unfinished second floor but tweaked the command so that the door wouldn’t open at all unless I willed it to.

Just to be on the safe side of things, I pushed thoughts of durability and iron into both doors and felt my soul essence pool dip and spilled out of my walls and rushed into the doors, fusing with them but otherwise doing nothing.

It did something though, and only time would tell. Next, I moved on to the most exciting part of dungeon design, the dungeon entrance. This was key, a dungeon entrance set the tone for the dungeon and would have the most impact on anything with intelligence that tried to enter my dungeon.

This would also confirm if I could claim some of the outside world as my own, with no small amount of trepidation I pushed some of my soul essence outside, and the world shifted before extending and patterns flowed into me.