The midday break, during which they watched the heartwarming scene of Ielo rescuing a squirrel, eventually came to an end, and Rei and his party decided to resume their exploration of the forest.
Unlike their previous aimless wandering, someone suggested that since a river—though perhaps it should be called a stream given its scale—flowed right before them, they might as well follow it upstream.
No one raised any objections. With a river present, it would be easier for Marina to use the Spirit Magic she excelled at, particularly Water Spirit Magic, so it was decided they would head upstream.
If there had been some clear method to explore this forest within the dungeon, they might have prioritized that... but since this was Rei and his party's first time challenging this dungeon, they had no particular guiding principle to follow.
"The river's gotten quite a bit wider. I was sure that if we headed upstream, we'd reach the source right away."
Spotting the silhouette of fish swimming in the river, Vihera muttered.
The river, with enough width and depth for fish to swim freely, could no longer be called a stream.
"Tributary... I'm not sure that's the right word given where we just were, but I suppose it's something like that. The river widening means more options for me in combat, so I'm happy about it."
"Gruuh!"
The moment Marina said their combat options would increase, Set let out a sharp cry as if that had been a signal.
Hearing Set's cry, everyone readied themselves to respond immediately to whatever might come.
"Because Marina said it."
"Oh, it's my fault? Well, you're right. In that case, since the opportunity presents itself, with Water Spirit Magic—"
Not letting Marina finish, Rei sprang into action.
He had seen the surface of the river flowing nearby bulging unnaturally.
What emerged as if breaking through the water's surface was a horse.
(A horse, water, a horse... a Kelpie!)
A C-Rank Monster, the Kelpie, which often dwelled in rivers, swamps, and lakes.
Rei had heard stories about them and eaten them in dishes before, but this was his first time actually seeing a Kelpie in person.
The Kelpie, with only its face above the water's surface, had its mouth aimed toward Marina.
Seeing that Kelpie like that, it would be impossible not to be suspicious.
Indeed, the moment Rei stepped in front of Marina, water was expelled from the Kelpie's mouth.
A Water Jet, or perhaps a Water Cutter.
Regardless, Rei swung his Death Scythe, infused with magic power, against the water launched at Marina in an instant.
The Kelpie's water attack undoubtedly carried considerable force.
It was a surprise attack... and one launched from within the river, its own territory, from a position of full preparation as an ambush.
But there was no way such an attack would work on Rei wielding the Death Scythe, and the water released by the Kelpie was deflected with ease.
Perhaps not expecting its attack to be blocked in such an ideal situation, the Kelpie froze for a moment with its face still above the water... and that would lead to the worst possible outcome for it.
Mirage that Elena released transformed into a whip, coiled around the Kelpie's neck protruding from the water's surface... and severed it.
Hiiihihihihiin!
Along with a massive amount of blood flowing from the severed neck, another Kelpie emerged from the river's surface a short distance away.
Family, friend, or perhaps a lover.
No one present could tell what kind of relationship the two Kelpies had.
But the newly appeared Kelpie was undoubtedly enraged toward Rei and his party, and acting on that anger, it tried to attack Elena, who had killed the other Kelpie...
"Gruuluh!"
The moment Set's cry rang out, the face of the Kelpie that had been about to spew water just like the first one burst unnaturally as if punched by something, and the water was released in the wrong direction.
One of Set's skills, the Magic Eye of Shock.
The power itself wasn't that great, and the Kelpie struck by it didn't appear to have taken any damage.
But as a sudden surprise strike out of nowhere, it was quite effective.
Hiihin!?
The Kelpie, having experienced its intended surprise attack go astray in an unexpected direction due to an unforeseen strike, hastily looked toward Elena again... no, the instant it tried to, it took a blow from Set, who had moved instantly to right in front of it, shattering its head.
Power Crush, one of Set's skills.
Having reached Level 5, that strike with its now fearsome power wouldn't have been limited to merely breaking the Kelpie's neck bones.
On top of that, Set was equipped with the Bracelet of Herculean Strength.
The synergistic effect of that Magic Item, which augmented physical strength, and Power Crush sent the Kelpie's head bursting apart.
(Should I say something like "what a filthy firework"?)
Rei thought that absentmindedly while watching the Kelpie's corpse being hauled up as it was being washed away by the river in Marina's Spirit Magic.
Though even if he said such a thing, no one would understand the reference.
"Two Kelpies, huh. Kelpie meat is delicious, so that was a welcome ambush."
Reliu had probably eaten Kelpie meat before. True to his words, he was smiling happily.
"I didn't think there'd be monsters in the river too. Well, thinking about it normally, it wouldn't be strange for there to be."
"What should we do? Keep heading upstream like this? There might be other monsters waiting in the river, you know?"
At Vihera's question, Rei hesitated slightly.
For one thing, they didn't know where the stairs leading to the third floor were.
Given that, there was a very real possibility that if they continued upstream, they would be attacked by monsters like the Kelpie that made the water their domain.
But after pondering for a moment, Rei decided to continue upstream, fully aware of that risk.
"Since we don't know where the stairs are, it doesn't really matter which way we go. And while river monsters are troublesome, we can handle them without much difficulty."
"...I won't deny that."
Vihera's slight displeasure was likely largely because if monsters were in the river, she wouldn't be able to fight.
Of course, it wasn't that she couldn't fight at all if she pushed herself, but fighting in the water was a considerable burden for Vihera.
There was no way she could perform at her usual level.
Moreover, Vihera specialized in hand-to-hand combat that leveraged her light body, so a situation where movement was difficult in the water meant she couldn't fight properly by any stretch.
For Vihera, it was only natural that she would want to explore the forest where she could move freely and fight.
"Well, even if we go upstream, not all the monsters that appear will be exclusively in the river. There are plenty of monsters that operate near the river, and watering holes inevitably attract many monsters, so why not count on that?"
Among monsters, there were some that could go without drinking water—existences Rei found a bit hard to comprehend—but the majority, as living creatures, naturally required water.
If they headed upstream along the river, encountering monsters that came to drink water was not a difficult proposition.
Naturally, when drinking water, both animals and monsters tended to let their guard down, and would often flee immediately if a threat approached.
(What Vihera is hoping for is that a monster, disturbed while drinking water, gets angry and attacks.)
Rei thought that while looking at Vihera, who showed signs of nodding at his words.
Indeed, Vihera appeared convinced by Rei's words, so his guess was not wrong at all.
"Anyone else have any objections? I won't listen to any complaints later."
Confirming that Vihera was satisfied, Rei asked the others, but no one seemed inclined to object.
Elena had Mirage for mid-range attacks and Wind Magic for long-range, and in the worst case, she could use her Sleipnir boots to fight even opponents in the river.
Marina excelled at Wind and Water Spirit Magic, so advancing along the river was actually what she wanted.
Byune was not the type to fight on the front lines to begin with; her main role was providing support from a distance, so having opponents in the river made fighting somewhat more difficult, but she still had effective means of attack.
Reliu... being an A-Rank adventurer bearing the alias Gale, with a skill called Wind Slash similar to Rei's Flying Slash, there was no problem.
Set and Ielo could fly, so that was also not an issue. ...Though Ielo wouldn't participate in combat.
(Actually, the Sleipnir boots are something Vihera needs far more than me or Elena.)
He couldn't help but think that, but the Foot Guards that came as a set with Vihera's boots were also Magic Items capable of producing blades of magic power from the heels, carrying significant meaning for Vihera's combat style.
For Vihera, whose main approach was hand-to-hand combat, the blade on the heel of her Foot Guards was a precious source of attack power. ...Though Magic Impact Palm was far more devastating in attack power than that blade.
Additionally, the Sleipnir boots, which allowed one to tread on air, were Magic Items that any adventurer—anyone, really—would desperately want.
While not as much as an Item Box, they were undeniably extremely rare items.
They were not something that could be procured immediately just because one wanted them.
(If I could grant the effect of the Sleipnir boots to the Foot Guards, that would be the best solution, but...)
Rei harbored that thought while heading upstream along the river, hoping to encounter a Sleipnir.
The Sleipnir, taking the form of an eight-legged horse, was an extremely rare monster, capable of galloping through the sky.
But he held a faint... truly faint hope that perhaps a Sleipnir might exist in this forest.
Of course, the reason he held that hope was that having encountered the Kelpie, a horse monster, in the river, maybe the Sleipnir, another horse monster, might also be present—a hope that could barely even be called a hope.
Even so, as long as the possibility wasn't zero, there was no harm in hoping.
"Alright, let's get moving."
At Rei's words, the party resumed their ascent upstream along the river.
Along the way, they spotted several deer—animals, not monsters—but they did not hunt them.
Deer meat wasn't bad by any means, but purely in terms of taste, monster meat infused with magic power was more delicious.
There was no need for Rei and his party to spend time hunting deer here.
Kyuu...
For some reason, only Ielo, riding atop Set's head, seemed disappointed that they couldn't hunt the deer.
"Deer, huh. There are probably plenty of other wild animals in this forest too—boars, foxes, raccoon dogs, and depending on the area, even bears."
"Judging from this forest, you're probably right, Rei. But... why would a newly formed dungeon have this much space? Looking at this forest, there's no way it could have just been created."
At Elena's words, Rei... no, the others as well, directed their gazes around.
Indeed, the expanse of this forest was undoubtedly larger than the cliff where the dungeon existed.
Had those stairs connected to some other space... or was the interior of the cliff spatially expanded, or was it something else entirely?
Rei couldn't determine the reason, but even so, he could understand that this dungeon was no longer a newly formed one.
"Probably, the dungeon grew without anyone finding it, and for some reason, it coincidentally connected to that cliff... that's likely the correct answer."
"That seems right. Of course, dungeons are still full of mysteries, so it's possible it was this size from the very beginning."
"...At the very least, when I challenged a newly formed dungeon near Gilm before, it wasn't this spacious."
"Ah, the Gamelion one."
Marina immediately recalled the events of that time from Rei's words, and an amused smile crossed her face.
Because Gamelion had gathered in that dungeon for some reason, that year's Gamelion ended up unable to line adventurers' pockets as usual.
The Gamelion meat from that time still sat in vast quantities inside Rei's Misty Ring, delighting the palates of Rei and his party.
Reliu, too, living in Gilm as he did, apparently had various memories associated with Gamelion, and he chatted while making their way upstream along the river.