The core was expanding steadily, gradually covering a wider and wider area. It was having a tricky time managing how much mana to spend on creatures and how much to use to expand its aura. The larger the aura the faster it regenerated mana and the faster it could create more creatures. However, if it expanded its aura too much while ignoring its guardians the core would be left without sufficient forces to defend itself. On the other hand, if it ignored its aura the dungeon would stagnate, and eventually, the core would be unable to create enough creatures to effectively defend itself.

With that in mind, the core tried its best to divide its mana in a way to maximize its growth. More creatures would have a more immediate impact in the form of new templates and more food which would mean more creatures and more total mana for the core. However, the core wasn’t a fan at endlessly producing more and more creatures. Fortunately, it didn’t have to make ants anymore, scorpions were much more powerful and it needed fewer of them to be effective.

The core had to make sure not to slack off on its defenses but it was still exciting to find several new things while expanding its aura. It was mostly just new plants that weren’t useful, the core’s grass was still all over the upper dungeon and still as far as it could tell did nothing. The core was certain it would find a use for the plants eventually even if it couldn't figure it out right away, plants were rather easy for it to understand anyway so it wasn’t much of a bother one way or the other.

One template that was giving the core significant trouble was the mouse template, it was making progress but it still felt like a long way to go. Mice were just so much more complicated than ants or even scorpions. The core was determined to get that pattern eventually, the mice would be another massive upgrade to its defenses similar to its scorpions replacing the ants. It had gotten lucky with the first one it had killed, which had become abundantly obvious recently as more and more mice made their way into the dungeon.

Killing a mouse was actually relatively simple for the core when its plans worked as intended. Two scorpions lying in wait out of sight would deliver venomous tail stings to a mouse’s eyes, once that happened the mouse was finished. This tried and true method served the core well but it was also hard to pull off. If the initial strike failed then the core had to try and wear down the mice until they succumbed to their injuries. The scorpion’s venom was still the best way to go about this but it was so much more difficult taking on a blinded and dying mouse than an angry one that could tell exactly where the pain was coming from.

The core had lost a third of its total scorpion population to one mouse after a botched ambush. It had made little adjustments to its setup, making the ambush positions lightly behind the tunnel entrances, and constricting the size of the tunnels a little bit. It had misjudged the proper size to make them at first but now the mice were moving along its tunnels in painfully cramped ways which would occasionally help a wandering scorpion caught out in the open. Other invaders besides the mice weren’t a threat to the dungeon anymore, they were just so much weaker than the scorpions.

The core gazed at the latest invader, yet another mouse, as it made its way down to the first ambush chamber. With its nose twitching the invader crept up to the new chamber, briefly withdrawing its head to scratch at the splotchy grass of the upper dungeon. Sticking its head back into the new chamber the mouse slowly crept forward-looking around for something. The scorpions struck in perfect unison under the core’s direction, twin stingers puncturing the mouse’s two eyes without warning.

The mouse reeled backward squealing and thrashing, the core carefully kept its scorpions back in the ambush room. The mouse was already dead and sending its scorpions out to finish it quicker was a needless risk. It had lost a pair of its scorpions to the death throes of a mouse already and it was just a needless risk as far as the core was concerned, watching the mouse’s agonized twitching to insure it died. When the cloud of formless food left the mouse did the core turn back to expanding its aura.

Another piece of the mouse template slotted into place as the core understood just a bit more about the species. The core was happy with its progress, it had expanded so much that the dungeon was now wider than it was tall. This allowed the core far more space to set up ambush points and forced intruders to wander the increasingly large dungeon to even attempt reaching the core. It had tried to expand upwards again but each time it tried there was an enormous drain on its mana reserves and the core was forced to retreat.

It still didn’t know why that direction was barred to it, but it had gotten a bit of a clearer picture of the surface from the memories of the mice. These memories were much clearer than any that the core had before and one memory that both intrigued and scared it was one of a mouse gazing up. The core had at first assumed that the area above it was just a really large cave but that did not seem to be a ceiling at all, just an endless expanse of blue. Lots of things about the area above confused the core, for one why was light so inconsistent? The stuff was constantly coming and going, one moment it's completely gone and the next everywhere. It had discovered that its core also produced light which was interesting but ultimately not of much use to the core.

The core felt the dirt start shifting off to one side of its dungeon, that was interesting, a few things had burrowed into the upper reaches of its dungeon before but it wasn’t very common. The core started debating about what it would be, it was probably just another earthworm, but it was hoping for another mouse. It didn’t usually get more than one of the creatures in a day, but it did happen sometimes.

The core then noticed that the area that was moving was rather large about the size of what a mouse should be. It eagerly waited for its next victim to dig its way into the dungeon, however, what came in was a little more than the core had bargained for. That is not a mouse, it had no idea what this terrifying new abomination was. The core watched in trepidation as an enormous head pushed its way into the dungeon, a forked tongue flickered out, and a sinuous body followed after. If the core could compare this new invader to something it would have to be the earthworm. Both had no limbs and moved in a similar wiggly manner digging through the earth. However the similarities stopped there, this new creature was massive, filling the entire tunnel with its bulk. This creature also had some features that an earthworm notably lacked, such as eyes and a recognizable mouth. The core had a wandering scorpion rush over to the invader, deciding that caution would be best as the tail of the creature still hadn’t entered the dungeon, the core deciding against attacking the creature head-on. Instead, it used an intersecting tunnel to come at the invader from the side.

The bulk of the creature slowly slid by the scorpion as it reached the invader. The scorpion bravely charged forward and lashed out with its trusty tail, Clink. The tail bounced off of the intruder, the core felt tendrils of dread slowly begin to sink into its mind. The scorpion was the strongest defender it possessed; if they couldn’t even harm this creature, the core was in very big trouble. Trying again the scorpion's tail lashed out again and again futilely trying to stop this new intruder. Eventually, the tip of the scorpion’s tail broke off, and the desperate core ordered it to attack with its rarely used pincers. This too proved useless, and one of the pincers was almost torn off as the scorpion tried to get a grip on the moving bulk of the creature.

The core felt cold as it watched the tail of this new behemoth slowly slide into view, It would need to go after the eyes of this creature. Its ambush chambers would hopefully work just as well against this new creature, and hopefully, the scorpions would be able to inflict a fatal injury. However something was off about this intruder, it took the core a few minutes to figure it out but eventually, it realized something, it wasn’t moving towards its core. Every other invader that had braved the dungeon had been fixated on going as deep as possible into the dungeon, towards the core itself. This new creature wasn’t behaving like that at all, it was just pushing its way across the dungeon acting like it hadn’t even noticed the core was there.

The core wasn’t sure if it was relieved to not be the target of the invader or annoyed at its apparent disregard for the entire dungeon. It settled on relief as its stubborn scorpion finally got a grip on the moving bulk of the creature, and was then promptly crushed against the side of the tunnel as it was dragged away.

There was a brief fear-inducing moment when the interloper paused at the entrance to one of the ambush chambers, but it merely flicked its tongue over the spot of the mouse’s recent demise and then continued across and then out of the dungeon. The core was frankly relieved that the encounter was over, but it did wonder why the invader hadn’t been attracted to its core as the other interlopers had been. Maybe the core was just so weak that it was beneath the creature’s notice? That was not a comforting thought for the core; it decided that it did not want any more surprise visits to its dungeon. They could all come in through the actual entrance or not at all.

With that in mind the core set about making a thick shell of stone around the upper portion of its dungeon. The lower part was already rock so it didn’t need to be changed, but the upper areas were all composed of dirt which seemed a little too easy for most creatures to dig through. The rock layer would be a pain as the core expanded but it would be well worth it if it kept out any other invincible invaders from entering the dungeon.

With that completed the core considered what else it could do to keep itself safe. It didn’t have any creatures that could harm that invader so it obviously couldn’t rely on its creatures to defend against this new threat, at least for now. Therefore the only option would be to make its core completely inaccessible to any potential intruders.

The core was already at the bottom of a deep pool of water but it didn’t feel like that was enough security anymore. Carefully it crafted a new layer of stone, completely sealing off the only tunnel that led to its core. The core finally started to relax, there was absolutely no way anything was going to get through that, rock was much better than dirt, absolutely no digging allowed.

Pausing the core realized there was something wrong, its mana wasn’t coming back. It had a brief panic attack wondering what had happened to it and blaming everything from ants to stupid invincible invaders for this. It finally realized that its mana was coming back; it was just really, really slow. Actually, it hadn’t had this mana regeneration this low since before it was drowning ants.

Acting on a suspicion the core broke down the wall of stone separating the core from the rest of the dungeon. Mana began flooding back in, and the core’s regeneration went back to normal, this was interesting. The core wouldn’t be able to completely seal itself away all the time but it could use it as a last-ditch attempt at self-preservation. For now, though it needed to keep growing, and to do that it needed as much mana as possible.