Crossing The Fourth Line

Since the day's early hours, the Loki Familia's five person party had been continuously battling monsters on the 58th floor. Usually, they would only have four or five hours of time once they made it here during their expeditions, partially due to their schedule, and partially due to the stamina that they lost on the floors that they needed to fight their way through to make it this far. This time, however, thanks to the borderline game breaking teleportation ability that Ais could make use of, they could focus a lot more on this ultimate frontier of the dungeon.

With deafening roars, massive numbers of mostly Valgang Dragons surrounded the party, shooting their fiery breaths and swiping at them with their claws and tails. For anyone else, this would have been a terror-inducing situation, but none of those assembled here had anything to fear. Every single one of them had ranked up to Level 6 by now, so these monsters, which were amongst the strongest Level 5 monsters that had been encountered so far, didn't pose too much of a threat.

Accompanied by calm and unhurried chanting, Riveria summoned an enormous blizzard that assaulted hundreds of the surrounding monsters and froze them to death, acquiring some breathing room for her party members in the process. Because she, Gareth and Finn gained basically no excelia from killing opponents as weak as these, they had mostly left the killing to Tione and Bete, who could still profit from the battles. This, however, did put both of them under a lot of pressure, so whenever they looked like they were about to be overwhelmed, one of the veterans would intervene.

With a small frown, the motherly Elf looked to the side, at her old Pallum friend, the Captain that they all relied on. For a while now, Finn had been pacing up and down nervously, the expression on his face anything but a positive one.

"What is going on?"

There wasn't even a need to ask whether or not something was wrong - after all, the answer to that question was obvious. So as to not distract the two fledgeling Level 6's amongst them, Riveria chose to whisper her inquiry, barely loud enough for Finn and Gareth to hear it.

Her words caused the former to stop in his tracks and to hesitate for a moment, then he sighed and responded just as quietly.

"Ever since we found that staircase leading further down, my thumb has been throbbing like crazy. I'm positive that should we descend there right now, things would go horribly wrong."

This revelation made Riveria furrow her eyebrows, and only after a while did she wager an educated guess.

"Is it because Ais isn't here with us? All the supplies that we prepared to brace the 'Glacier Territory' are with her. So without those, we're completely unprepared for the potential environmental dangers. If it's not that, it might be an especially strong Monster Rex."

Even though what she had said did make sense, Finn could only shrug and shake his head helplessly.

"I don't know. Both of these don't feel entirely correct, but I just can't put my finger on it. I guess for now, we should just wait for Ais, Tiona and Isaac to join us, then we should be able to brace the risk."

From the side, Gareth had been listening in all along and nodded in approval. He usually left all of these decisions to his two old friends to make, as they were considerably more talented at these mental gymnastics. While he wasn't a musclebrain by any means, thinking things through thoroughly just wasn't the area that he most excelled at. It was neutral territory for him, so there was no point in arguing with the field's experts.

Unbeknownst to the three of them, somewhere on a staircase leading down to the 59th floor - far out of anyone's range of perception - an athletic woman with a frosty expression was leaning against one of the dungeon's walls, paying attention to their conversation. She had relatively short, blood-red hair and green eyes, and was about half a head taller than Ais. Her attire seemed like a patchwork put together from multiple adventurers' outfits, as her armour pieces didn't match, and neither did the clothing underneath.

'Why is there someone down here!? From what my master told us, none of the familias of Orario should have been here at this time. Then why is the Loki Familia here? I need to report this. Thankfully, they don't seem to be planning to head any further down for a while, so I will let my master know about this during our next scheduled meeting.'

Although she looked unperturbed on the surface, the woman's heart was all but calm. Never before had her master's information been flawed, so when she had noticed the muffled sounds of intense battle coming from the 58th floor, she had initially frozen up in disbelief for a couple of moments. Only after quite a while had she been able to come up with a plan of action on the spot.

'Oh well, for now, I'll continue to observe them. Once they leave, I'll go back down to continue my work.'

-----

The 47th and 48th floors still fully consisted of connected caves, but this time, the temperatures were even a little bit colder than before - well, basically, it was still extremely hot. What had changed was that the carbonized tree-look had been swapped with sandstone and a hell of a lot of sand. For now, the environment wasn't a problem at all, so Isaac could fully focus on researching the various new monsters. Just like in the first half, seven different species populated these floors. Well, and the Monster Rex, Balor, who wasn't even close to respawning.

There was one more noteworthy detail about the 47th floor - it was also referred to as the 'Fourth Line'. Just like the previous ones, this one marked the spot where regular adventurers would usually gain the qualifications to rank up to Level 5. It was also the very last 'Line' that there was at the moment, simply because not enough people had reached Level 6 yet to determine which floor should be called the 'Fifth Line'. Maybe nobody had even reached that floor yet - after all, most of the outstanding adventurers of these times had only made it as far as they did by slaying variants and Monster Rexes.

Occasionally, Isaac would stumble across groups of hundreds of Desert Lizards, who seemed to just be waiting for potential prey to enter their territory. They weren't rare by any means, but they didn't wander around like most monsters did. Also, they looked quite unassuming - two meter long, earthen-coloured salamanders whose only strengths were their physical bodies just weren't much of a surprise or challenge to anyone who had made it this far. Their stats could reach up to C-600 / 14,250, and their only real tactic was to swarm their enemies and bite them to death. Yes, it was that simple.

But even unremarkable monsters like these couldn't escape the - arguably mad - scientist's grasp. Even trivia such as whether or not they could shed a part of their tail just like some of the reptiles from Isaac's past world were thoroughly put to the test. For the record, they could. Many poor lizards had attempted to retreat and regroup with their brethren, and displayed this 'diversion' ability in the process.

The next most numerous were the Fomoires. Whenever any adventurers thought about the Desolate Frontier, they were what came to mind first, simply because they roamed absolutely everywhere in this latter half. In essence, they were similar to Minotaurs, the only difference was that they had goat heads instead of cow ones. Also, as probably expected at this point, they were far stronger, with their Strength and Endurance reaching up to C-650 / 14,650. The groups that they formed usually would consist of close to a hundred individuals.

They could also use rudimentary tactics and some natural weapons found in the dungeon, such as sticks and stones, or the weapons of slain adventurers. Still, because barely anyone made it all the way down here, these occurrences were now few and far between. Whenever a familia ventured this deep, they were usually accompanied by experienced and strong veterans, who would clean up any opposing monsters or at least secure the corpses and belongings of their fallen from the monsters' maws. So, the sight of Fomoires carrying manmade weapons had only been prevalent back when these floors had been the furthest that anyone had ever made it.

Fomoires were extremely simple-minded and relied far more on their muscles than their smarts - needless to say, they didn't pose much of a challenge, not even to regular adventurers. Once one knew how to deal with the Minotaurs, one basically already knew what to expect from these goat monsters.

Occasionally, massive herds of Old Bisons would cross Isaac's path. They followed in the footsteps of all the other monsters that were just scaled-up, stronger versions of animals that he knew from his old world. Besides the fact that their hides were quite durable and one of the favourite materials to make protective clothes from for the higher Level adventurers, there was almost nothing else to mention about them. Well, besides their Endurance stat, which could reach up to B-700 / 15,050.

Even some more reskins could be found on these floors, in the form of Sand Worms. They were - obviously - stronger, desert-themed versions of the Dungeon Worms that could be found in the Middle Floors. They still attacked from within the dungeon's various walls, the ceiling and the ground, just like before. One thing that set them apart was that they apparently could move far more quickly when submerged in sand, so whenever Isaac entered bigger caverns that contained massive amounts of it, they would behave like rabid piranhas in water. Their Agility could reach up to B-750 / 15,450. Their one saving grace was that they did provide him with stat points in the single digits again, but only for the first few kills.

With just as original of a name as the Sand Worms, the next strongest ones on the list were the Sand Scorpions. Initially, Isaac had expected for them to be just like the Old Bisons, but they had given him a positive surprise - aside from the now far more noticeable amounts of excelia that they provided. The scorpions could actually fire poisonous needles from their tails, at a speed that made it extremely difficult to evade. Even Isaac had almost been grazed by one of these attacks, so it was no wonder that usually, adventurers would need to carry some sorts of Elixirs with them or to have a competent healer along to handle the detoxification process.

Because the poison got augmented by the scorpions' mana, their Magic stat was quite high - it could reach up to A-800 / 15,850. Their Endurance was the same, which showed in their resilient chitinous carapaces. Still, just like most lifeforms that relied on these, once their defenses were broken, they were living on borrowed time and could only wait for their deaths. In the Sand Scorpions' case, this bleeding-out process took exactly 12 minutes and 41 seconds. To test this, Isaac had kept one of them in such a state and observed it with his Eyes of Hermes while continuing his research on other specimens.

Although the Sand Scorpions had been a pleasant surprise, the following Vulture Hunters, sadly, were anything but. They were far bigger versions of vultures from Isaac's past world, nothing more. Admittedly, they were a lot faster, more powerful and more resilient than those birds, but that was what was to be expected from a monster. Aside from their Magic, all of their stats were at A-825 / 16,050. Only when Isaac made it to the 49th floor could they even make use of their full abilities, as the larger caverns that they had resided in previously had just been far, far too small compared to the seemingly endless singular room that the last floor of the Desert Frontier consisted of. But even then, due to Isaac's Anemoi Steps, they had nowhere to escape, and their mobility advantage was all for naught. Even if he hadn't had such a convenient Magic at hand, the bow and arrows in his inventory would have been far more than sufficient to snipe them out of the sky.

Lastly, there were the Basilisks - and they were finally relatively interesting opponents to look forward to again. While they weren't able to cause death with a single glance and neither could they petrify their opponents, like the various myths from Isaac's old world claimed, this world's kings of the serpents were still extremely deadly.

Their bodies varied in size from about twenty to fifty meters in length. They weren't actually serpents, but rather eight-legged, wingless dragon type monsters. Needless to say, the toughness of their scales was exceptional, and they also had fire breath attacks in their arsenal. But those weren't what made them so dangerous. Rather, it was the constant flow of overpowering poison that flowed from the gaps in between their scales. In other words, they were wet and slippery, even in this climate. They left literal rivers of poison in the wake. Not only would anybody who touched these toxins be paralyzed, but if they weren't treated within a specific timeframe - which differed depending on the victim's Endurance - whoever touched the poison would simply die. Most regular Elixirs weren't able to treat it, so it was quite expensive to get rid of its effects. During expeditions, parties would usually let their mages deal with the few basilisks that they would inevitably encounter. All of their stats were equal and could reach up to A-850 / 16,250.

It was at this point that Isaac ran into a bit of a problem - one that he had ignored previously, as there just had been no time at all to deal with it. His weapon, the perfectly weighted sword that he had managed to buy some time ago… it simply wasn't strong enough to deal with the Basilisks' scales. Even after a single clash to test their durability, the sword was already close to shattering, so he had no choice but to put it away and into his inventory. Ais had long since advised him to upgrade his equipment once again, and he had intended to take her up on this offer. He had even planned when to do it… but due to the attack on his students, his plans had changed.

All of this didn't mean that Isaac was out of options, however. Just using his body to attack directly would be enough to obliterate these enemies, even when he restricted himself to the same stats as the monsters that he was facing. The poison that he would come into contact with would be a bit of a momentary headache, but not an obstacle that was impossible to overcome. But thankfully, there were still other options.

Back during his battle with the Black Blade, he had slain the Petbe Familia's Captain, and also obtained his weapon in the process - a khopesh made out of a material that could easily overcome most Monster Rexes' defenses, and obviously the Basilisks' scales too. The problems with it were that Isaac personally preferred regular, bog-standard swords over these sickle swords, and it also hadn't been custom-made for him, so it felt a bit awkward to use.

'Oh well, this will have to do for now. I'll see to it to commission a new sword with that blacksmith that Ais wanted to introduce to me later in secret. For now, time to forge ahead.'

With a reluctant sigh, Isaac swapped to Mosi's khopesh and swiftly continued his research. By the time that he found a staircase leading towards the 50th floor, another two and a half hours had passed. Still, he didn't immediately descend, contrary to what he had done all of the previous times. Instead, he continued to stay here on the 49th floor for another forty minutes, during which he stopped restricting his stats, as his research was already complete.

The reason as to why he had stayed in place for now was that he hadn't unlocked the fourth Level's Hunter-series Development Ability yet, and all monsters past this point would be at Level 5 already. Originally, he had expected to only need to slay 15,000 Level 4 monsters, but only when his monster slaying achievement arrived at about 20,000 did the Development Ability finally grace him.

'This is insane! If this one follows the previous Levels' requirements, one would need to slay 20,000 Level 4 monsters in a single day, while still staying at Level 4 oneself. No wonder nobody has ever seen this one before. For regular adventurers, it might as well be impossible to achieve.'

Isaac couldn't help but click his tongue in disbelief. The increase in required kills would have been quite exhausting even for him to deal with had he not obtained the Divine Being buff. Sure, he still would have made it in time easily, but he would have been considerably exhausted by the end of it.

'That said, if I could go back in time… wait, I can actually do that. Let me rephrase that. If I chose to go back in time, I would still not choose any other Development Abilities to focus on.'

Smiling smugly to himself, Isaac glanced at the details of the Development Ability that he would soon obtain. His intuition told him that there would most likely be a nice surprise waiting for him once he found the time to grind all of them to their maximum grade.

[ Veteran Hunter (I): When battling a monster one has already gained excelia from previously - 8% increase in all stats, 8% increase in excelia gained. ]

-----

After she had brought the students back to the training courtyard, Ais bid her farewell to them and quickly arrived on the 57th floor, right next to a staircase leading to the 58th. What greeted her were the battered figures of Tione and Bete, as well as her three mentors, whose clothes were still mostly spotless.

"Took you long enough."

A low grumble escaped the Werewolf's mouth while he was resting on the floor, trying his best to recover from all these hours of intense fighting.

The golden-haired beauty's mood, which had been excellent so far, took a slight hit at this tactless remark, and the lid of her right eye twitched almost imperceptibly. Still, instead of lashing out, she chose to ignore Bete and focused on the rest of the party instead, sporting a slight smile.

"Everyone, gather around."

Merely a second later, they were already back in yet another one of the familia's training courtyards. These were simply the easiest excuse that could be found to mask their dungeon delving trips, so there was no need to come up with a new one just for the students.

Now that she was finally almost done with her transportation services for the day, an excited grin appeared on Ais' face.

"I'll go and get Tiona. After that, I'll stay with Isaac for a bit."

Leaving these words behind, the girl disappeared into thin air. Riveria had only just opened her mouth to say something, but then she shook her head and smiled wryly to herself.

'There is no need to worry, they won't make it that deep anyway. She has been looking forward to spending some more time with him all day now, so I'll avoid burdening her with 'that' for now.'

Seconds later, Ais reappeared with a slightly disgruntled Tiona, before vanishing yet again, her eyes sparkling with happiness. Slightly curious, Riveria approached the usually cheerful Amazoness.

"How long does Isaac plan to stay in the dungeon? And how far has he progressed?"

It only took a couple of breaths for Tiona to rebound from her less than optimal mood, and a bright smile soon spread across her lips. She giggled haughtily in Riveria's face, and started to brag about Isaac's achievements a little.

"Hehe, we've just arrived at the 50th floor. He said that he would pull an all-nighter today, so I wouldn't be surprised if he broke our floor record."

She hadn't known that Isaac had originally planned to surprise his allies with this achievement, so she revealed it all without hesitation. Well, she couldn't be blamed for this blunder, as he hadn't communicated these thoughts to her at all. In fact, he had behaved somewhat distantly from her. Tiona wasn't that much of an idiot, and she had long realized that the stronger that Isaac became, the more of her unwanted advances he gave the cold shoulder to. When she was alone, she would sometimes sit in depressed silence for a few minutes, simply because her mind had already realized that there probably wasn't a place for her in his heart. Still, whenever she saw him achieve brilliant feats of martial skill and strength, her Amazoness-self acted up again, almost overpowering her reason. The body and heart wanted what they wanted, and only time would help the harshness of reality to truly settle in.

While falling in love was easy, falling out of it or coming to terms with an undesirable development were extraordinarily difficult.

Suddenly, a pained groan interrupted Tiona's stray thoughts.

"Captain!? What's wrong?"

Her sister, Tione, had already rushed to Finn's side. The usually steadfast Pallum had grabbed his right hand's thumb tightly. His expression, for a moment, was not as calm and unperturbed as it usually was. This didn't last for long, however, and quickly, his face returned to normal. With an appreciative smile in Tione's direction, clearly grateful for the worry that she had shown, Finn explained what had happened.

"I'm fine, my thumb has just started to throb a bit more intensely than usual when I heard that Ais and Isaac might make it to the 59th floor alone. I've been having a very bad feeling about that floor for a while, and it seems like my intuition doesn't like their current odds one bit."

A deep breath later, his gaze hardened and he turned to Riveria, Gareth and Tiona.

"We can't communicate with Ais and Isaac while neither of them are present. Bete and Tione are too exhausted, so the four of us will have to do. No matter what, we have to reach them before they arrive at the 59th floor. Let's move out, at full speed!"

By the time that his last words had left his lips, the four had already charged out of the Twilight Manor, at a speed too fast for most people to even notice them.

Moments after they made it back into the dungeon, Tiona frowned heavily and asked the question that had been on all of their minds.

"What if they won't take the same path that we did? We might not even make it in time then, even if we get to the 58th floor first."

With unhappiness written all over his face, Finn heaved a forlorn sigh.

"I know. Our chances are abysmal, but should we fail, we'll at the very least be able to tell ourselves that we tried our best."

His reply didn't inspire confidence, but there honestly wasn't much of a bright side to look at.