The moment I stepped on the fifth floor, I was greeted with pain. It wasn't sourced from an attack — not for the lack of trying, as every inch of me had been surrounded by monsters. Flying insects, giant monsters, armored ones, crowded enough to cut each other's path.

No, it was the very breath I had taken that had hurt me, burning my lungs like acid.

[-17 Health]

That wasn't the only source of pain, as the moment I stepped in, I found myself in waist-deep water, and the amount that slipped burning like acid. Luckily, I was prepared for that, and jumped on the metal wagon I had created. That way, not only did I not have to fight buried in waist-deep water, but I was also safe from the underground attacks.

I appreciated it. While the underground attackers weren't any stronger than the others, their attacks came from a different vector, forcing me to pay attention to them as well. The situation was complicated enough, with my vision dropping to almost three yards.

Things would have been far more complicated if my armor couldn't just shrug off all the ranged attacks. I danced with my spear in hand, the improved alloy easily piercing even the armored shells thanks to the blue glow sticking around the weapon.

I stayed on top of the wagon, fought with a speed I had never done before as I pushed my Rare skill to the limit, not even finding a moment to grow a plant. The monsters were simply too many in numbers. Maybe I should return to the fourth floor to replenish my Health, to avoid a dangerous situation. It was difficult to count, but I might be killing a dozen monsters every second.

But, before I could make such a move, I was greeted by a very welcome notification.

[Level 40 - 41]

[+2 Vitality, +2 Strength, +2 Dexterity]

That was enough reward for the first expedition, I decided as I jumped through the gate, returning to the fourth floor, to adjust my plans.

The first thing I did was to open one of the silver containers to consume a dense nutrition bar, replenishing my Health. The fact that the very air of the dungeon was dealing damage to me was not something I had expected.

I couldn't help but shiver as I imagined what would have happened if my weapons and armor weren't immune to corrosion. Would have they just melted away and left me defenseless against the monster horde, all the while the very air itself burned my body.

Yet, even as I processed all the ways I had gotten close to the dungeon, one thing was clear. The dungeon was not unlike a puzzle, with each level increasing the difficulty, but one that was easily dealt with as long as one learned the appropriate lessons from the earlier floors.

The only problem was that I wasn't entirely sure I was learning the 'right' lessons. Even as my skills improved, which unlocked new, more complicated recipes, every single one of them had been designed for usage by individual warriors. Not even a siege weapon, let alone anything more complicated. Even the carts and other logistic items were not included.

"No time for such pondering," I spoke aloud, disrupting my own train of thought even as I stood up, ready to prepare for the second invasion. As much as I wanted to return to the base and create a few plans, I needed to confirm a few more details about the fifth floor.

However, first, I needed a mask. Luckily, I had already experimented on the poison while I was trying to isolate it, and knew two things about it. Silver worked well to neutralize it, and so did heat.

Fashioning a breather based on those two principles wasn't too difficult. The silver part was trivial, and even the heat part was not too difficult. I just made sure to heat up the outer layer and add an insulating layer in between.

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I made the silver part detachable as well, so, if needed, I could always use my sole magic skill to heat the mask back up. I didn't see that coming up, but there was no harm in being prepared.

"Now, the tedious part," I said even as I went back to the fifth floor, once again resisting the pile-up of the monsters. My breathing was once again uncomfortable, but this time, not every breath resulted in a loss of Health, so I chalked it as a success.

So, I stood on top of the war wagon, fighting against a veritable horde, their corpses piling around before they disappeared periodically. They presumably left skills behind, but I didn't have the time to check the waters for those.

None of them were able to touch me, but that didn't make their presence any less intimidating. As I fought against them, I started to understand why dungeon breaks were such a dangerous subject even more viscerally.

Alone and wearing the appropriate gear, the insect monsters were not a threat despite their great number. After all, there was a limit to the number of beasts that could attack me at once, and the disparity in equipment and mobility prevented that from turning into a problem.

Yet, I could easily imagine the same amount of beasts overwhelming the defenses of the town with ease. I sighed even as I continued to fight, dealing with the endless swarm I had triggered. Thrice, I needed to return to the fourth floor to rest, and during one of them. I went back to the second floor to check the dungeon hunting.

I was still afraid of a sabotage attempt from the other guilds.

During the third trip, the numbers in the swarm finally started to lessen, but it wasn't the only pleasant surprise. Another pleasant notification appeared.

[Level 41 - 42]

[+2 Vitality, +2 Strength, +1 Dexterity, +1 Essence]

"Finally," I cheered when I killed another beast, only for it not to be replaced by another attacker. At least, not a melee one. The ranged attacks continued to rain over my armor, but they were easy to shrug off.

I could have moved to hunt them, but instead, I returned to the fourth floor brought back a large sapling, and used Nurture to grow it.

[-96 Health]

[Nurture (Epic) 96 - 97]

Soon, I was looking at another towering tree. The additional notification was welcome. However, the moment I pulled back, the tree started to die, which showed that the same tree wasn't able to resist the corrosion of this level.

"That's not good news," I muttered. Exploring the fifth floor without the assistance of the trees was not acceptable.

Luckily, its degradation was not instant. So, I quickly raised six more trees, surrounding the gate with a nice field, which finally expanded my vision. It was a welcome change, as it meant I wasn't fully blind.

With the expanded vision, dealing with the ranged attackers was easier. The only problem, I had to periodically cure the trees. The expanded vision was worth the trouble, and the occasional points I received from the skill were well worth it.

Unfortunately, there was no chance that the trees would survive in my absence, which was not acceptable. I needed a more permanent solution.

However, before I started that, I made several quick trips between the fourth and the fifth floor, using the excess iron to create a raised metal platform surrounding the gate, not unlike a pier.

Constantly walking through corrosive mud was not my idea of a good time. Only after I had finished setting up the area, I turned my attention back to the trees. I was tempted to try using Epic Nurture to somehow increase the poison resistance of the trees. I knew that was possible, as some of the farmers had that as a Perk.

But, after helplessly trying that for half an hour, I paused, realizing the obvious pitfall I had fallen into, constraining myself to the System because of convenience.

Why not use a technological solution, one that many startups had been trying to implement on the scale before the Cataclysm.

Hydroponic farming.

I created several huge metal boxes, and filled them with soil from the fourth floor. Then, I set up another steam engine to pump water through silver heated filters, weakening the poison considerably.

The anti-corrosive floor meant that the roots of the tree couldn't grow just as deep, but that deficiency was easy to deal with using Epic Nurture. Which meant, an hour of effort was enough for me to create ten layers of trees, allowing me to set up a base successfully.

Once that was done, I scooped the skills from the water. Every single one of them was Epic, and none of them was currently usable for me.

I stored them back on the fourth floor before returning to the fifth floor, spending most of my time working on my base. After all, with the way things were, trying to explore the fifth floor was not exactly a time-efficient action.

Especially since I couldn't simply spread the trees.

However, my plans had been disrupted when the dungeon mist had suddenly split into two.

Revealing a gargantuan insect, charging forward!