If asked to name a beginner monster, the majority of people will respond with slimes. They appear in the vast majority of young dungeons, and in their basic form are weak enough for an untrained child to dispatch with ease. Even the largest form, the hyperbolically named emperor slime, is a mere level five monster and can be defeated safely by any adventurer with more than a few weeks of training. Specialised slimes that have evolved towards a specific element can be marginally more dangerous, if only because of their greater range of attacks. Since there are no higher level species of slime, it is common for a dungeon to start life as a slime type, then re-specialize as it grows.

- Excerpt on slimes, from the book Dungeon Critters

"Show me information on the... Umm... Show me information on all monsters on the sixth floor."

Unnamed <Error>
HP: 80/80
mana: 15/15

The slime blobbed cutely. The dungeon stared. Whatever had it done this time? Firstly, it would help if it had some way to refer to this... error. Since the messages kept referring to things as unnamed, that implied that they could be named. "Slime, your name shall be Blobby." The slime blobbed in polite incomprehension. "Show me the information on Blobby."

Blobby (<Error>)
HP: 80/80
mana: 15/15

Ok, that was a slight improvement; it had something to call the slime now. Blobby was very definitely a type of slime that was stronger than the emperor slime, albeit no more intelligent, but whoever or whatever was sending the messages didn't seem to know what it was. Maybe it was a monster that wasn't available for purchase with points no matter how many floors the dungeon had? If dungeons weren't supposed to be able to produce them, then there wasn't any reason for whatever was sending the messages to know about them.

Until now the dungeon had been searching for ways to unlock things without spending dungeon points, but this was the first inkling of realisation that it may be able to do things that weren't available with dungeon points to begin with. It had been too rigid in its thinking. Nevertheless, first priority was given to populating the sixth floor with these new type of slimes; the dungeon didn't want to risk any more insufficient mana circulation problems. With that done, it began reclaiming the area it had lost of the surface. Perhaps this time with its upgraded core it could reach out further, and with its improved intelligence could glean more clues from what it found.

The dungeon had once tried to send monsters outside, only to watch them immediately disintegrate. That also posed questions. It had claimed the outside surface, so why did walking through the entrance count as being outside the dungeon? It couldn't be a simple matter of requiring the dungeons mana to survive; the dungeon had already witnessed monsters surviving weeks of mana depravation. Sure they starved in the end, but they didn't immediately disintegrate. A quick night time experiment confirmed that it wasn't sunlight that was the problem, but it did tell the dungeon what was. Watching the mana as the monster disintegrated revealed it was exactly the same as the attempted purge when it had introduced monsters to the wrong floors. Well, the dungeon knew what to do about that! It sent another slime out, and pushed.

Warning: Dungeon stampede in progress

That was a bit harsh. It was only one basic slime. That hardly counted as a stampede. Interesting that the messenger had a name for monsters leaving a dungeon though, so obviously they must be permitted outside dungeons in some situations. For the next experiment, the dungeon attempted to create a slime directly on the surface.

Error: Attempted to summon a monster outside of a legal floor.

The coalescing mana burst apart, despite the dungeons best efforts to hold it together. It seemed like fighting against the messenger to hold together a monster it was trying to erase was considerably easier than fighting against the messenger trying to prevent it from spawning a monster in the first place. But having overcome its accidental near death experience, time was once again the one resource the dungeon had in abundance. It could afford some practise.

Error: Attempted to summon a monster outside of a legal floor.
New skill unlocked: [Improved Mana Manipulation]. You can control more mana, over longer distances and with more force.
Incongruity detected: [Improved Mana Manipulation] not available for purchase until dungeon has ten floors. Resolving conflict... Purchase requirements for [Improved Mana Manipulation] reduced to six floors.
Error: Failed to prevent summon of monster. No rule to handle this situation. Taking no further action

Amusingly that didn't even earn it another errant mark; the messenger simply couldn't handle the fact that the dungeon had resisted it. Were normal dungeons always so obedient? Surely they tried mixing things up and experimenting a little once they grew a bit? The dungeon did have to fight hard against its instincts the first few times it tried to be naughty, so perhaps most dungeons just never had a good reason to question their instincts.

Mana density on the surface was no lower than the dungeons first floor, so as it expanded back to its previous size, the dungeon placed small slime communities. Out here in the open the dungeon could clearly see the groupings of slimes pulling mana currents towards them, forming pretty patterns in the previously stagnant mana.

New skill unlocked: [Improved Mana Perception]. You can see more detail in mana and perceive more subtle movements.
Incongruity detected: [Improved Mana Perception] not available for purchase until dungeon has ten floors. Resolving conflict... Purchase requirements for [Improved Mana Perception] reduced to six floors.

That was convenient. The dungeon hadn't even been trying for a skill there, it just wanted to better understand how its monsters interacted with background mana. Now that it could see far more clearly it saw that monsters didn't quite 'eat' mana, but rather 'breathed' it. They clearly drew mana in but did not simply consume it, instead expelling mana of a different type. Lesser in quantity, but denser and of higher quality. Almost like they were compressing it, and in fact what they were doing naturally looked very much like what the dungeon had tried to accomplish with force when it had reinforced its core. Or squished its stone. In fact, this sort of mana compression seemed to be at the base of many processes. Even summoning new monsters spun them into existence from a coalescing cloud of mana.

Then what was its mana pool? Currently sitting at 20/20, it knew that was mana stored away in the core, but for what reason did it need it? It could control all the mana in its domain, so why not just spin a monster directly from the ambient mana? Summoning another slime, the dungeon watched the clump of mana leave its core, slip through stone directly to the summoning site and coalesce. The dungeon itself had made no effort to move that mana. Was this the messenger again? The dungeon had been born with a skill called 'spawn', so perhaps that was what was allowing it to create things. The dungeon had already noted that summoning was similar in feel as asking to view information, so the same thing that was displaying messages was also doing all of the heavy lifting when doing... dungeon stuff? So if the dungeon started to create its own monsters, could it bypass its maximum mana cap?

As it continued expanding its territory, the dungeon spent its time carefully observing the monster summoning process and attempting to replicate it. Slimes were by far the simplest of its monsters, being pretty homogeneous and not bothering with such complicated things as internal organs, but even a basic slime was beyond the current abilities of the dungeon. It did however learn that it could build pseudo floors on the surface. At each of its slime settlements the mana at the centre had reached a level high enough to support big slimes and iteration of that discovery had led to rings of population around its entrance: A ring of basic slimes on the outside, followed by big and then giant slimes. With that, the mana density inside the dungeon had increased so substantially that even the first floor now supported a population of king slimes. Of course, the messenger objected with its usual level of violence but with the dungeons improved control over mana it was now practically no effort to resist any attempts at erasing its monsters. With the improved density and mana control, the dungeon had also effectively rendered its official rate of mana regeneration moot; by manually channelling mana into its core it could regenerate the full 20 cap in minutes, a trick which sped up the summoning process massively.

Having completely taken back its previously claimed area, the dungeon revisited the ruined village. This time it could apply far greater understanding to the place, realising that some massive disaster had fallen without warning. Given the lack of animals or plants in the dungeons territory it was obviously not merely the village that had experienced disaster and neither had it specifically targeted higher forms of life. The ruined state of the village told that whatever had happened was long ago, but not so long that large wooden furniture was not recognisable for what it was; probably decades but not centuries. And the fact the village had lain undisturbed for all this time suggested that the area of effect was likely far larger than what the dungeon had claimed. The roiling sky, which in no way appeared natural, certainly covered as far as the dungeon could see. With no evidence either way, the dungeon was unsure if that was related to whatever snuffed out these lives. The dungeon knew that even if it continued growing, it was unlikely to find anything still living but might at least find more clues as to what happened or what it could do next. Putting its upgraded core and improved mana manipulation to use, it continued to grow.

The dungeon continued to grow its slime population, and started merging more slimes into larger forms on its official floors. The messenger just referred to them all as <Error> regardless of their level. In addition, the dungeon found that merging these unknown species together gave inconsistent results. There was some variation in their sizes and stats. Its... for want of a better term 'proper' monsters had completely deterministic stats. They were all summoned exactly the same. But now that it was running off the prescribed rails some individual differences were starting to set in. Observing the flow of mana within the slimes, the dungeon concluded that they were not in fact unique species and that everything was a single species of slime in which only the slimes mass differed. The 'species' only corresponded to the amounts of mass appropriate to the mana density of specific floors. It didn't make a huge difference, but it did presumably mean that the dungeon could merge slimes together as much as it wanted. Within reason, anyway. The newest slimes it had mashed together were too large to fit down corridors, ending up confined to larger rooms. On the bright side, this was doing wonders for mana density. Without the messengers cold logic it was hard to judge what the equivalent floor count would be, but it must be approaching ten by now.

The dungeon was distracted from slime time when its lowest floor suddenly begun an ominous creaking. Did its slimes get so fat the structure was giving way? Looking around in panic the dungeon couldn't see anything untoward, so what was... Interrupting its train of thought a patch of wall on the bottom floor shifted, along with a slight colour change. The dungeon recognised this; it was the compressed dungeon stone it had created previously. The ambient mana had reached a level high enough for the dungeon stone on this floor to transform on its own, the affected patch expanding and being joined by others. Phew, that wasn't a problem at least. But it did raise the disturbing question of if something similar would happen to the core. If the dungeon was growing floors in the usual pattern would it have been prevented from buying new floors without first obtaining appropriate levels of core reinforcement? The dungeon would need to make sure the mana density never got high enough for what it had deliberately done to its core before to happen spontaneously. Hopefully it would feel at least some warning signs but its core was still scarred from its first upgrade, so probably not a good idea to risk it. The dungeon decided to not do anything to encourage increased mana density for a while.

This greater background mana did do wonders for the dungeon's intelligence. Despite its mana control not having been artificially inflated further by any new skills granted by the messenger, it felt better able to apply the abilities it had. As such, it took another shot at manual monster summoning. And, after some practise, it succeeded. The resulting slime had one less HP than a regularly summoned slime, adding weight to the theory that the monster uniformity was imposed by the messenger's summoning process, but beyond that appeared identical. The dungeon thought that a manual monster summoning was certainly off script enough for the messenger to throw out an error or complaint about incongruity, and it wasn't disappointed.

Warning: Monster summoned within dungeon territory without input from dungeon system. Searching for overlapping dungeon systems... None found. Summoning source unknown.

Just a warning then. Apparently what the dungeon had been calling the messenger was a 'dungeon system', whatever one of those was, and from the sounds of it there were other dungeons each with their own dungeon system. Did that mean there were others like it out there in this world? Would they be stranded and unable to grow? Or were they growing their own really big slimes, or coming up with new loopholes this dungeon hadn't thought of? Also, continuing to call the messenger 'the messenger' was a bit inaccurate now that the dungeon knew it handled summoning and other tasks it thought were automatic. From now on it would be 'the system' instead. For that matter, the dungeon itself was unnamed. If there were going to be other dungeons, it would no longer be 'the' dungeon, so it should give itself a unique name too.