What Rei and Set saw upon arriving beneath the World Tree was a completely unexpected sight.
Even on the way here, Rei had been able to see that the leaves on the upper portion of the World Tree were withering. But now that he stood directly beneath it, he could see that the damage extended far beyond the canopy—many more leaves had withered throughout. And above all else...
"What is that..."
At the end of his gaze, something enormous clung to the trunk of the World Tree.
It was roughly twenty meters in length, and at its widest point, nearly ten meters across.
Rei had muttered the question under his breath, but he actually knew what it was—or at least, he knew of something similar.
Back when he still lived in Japan, he had seen such creatures nearly every year.
And the massive hole at the base of the World Tree confirmed where the creature had come from, backing up his suspicion.
It was a creature that appeared every summer. Something that could even be called a summer tradition—though normally, it was nowhere near this large.
"...A cicada?"
Yes. What lay at the end of Rei's gaze was unmistakably a giant cicada.
It had ten legs in total, five on each side, and something resembling a tail. Even so, its basic form was that of a cicada—or rather, since it was currently in a pupal state on the verge of becoming one, strictly speaking it wasn't a cicada just yet.
Of course, what lay before his eyes wasn't a cicada in the truest sense. As far as Rei knew, no such thing as a twenty-meter cicada existed.
For that matter, cicadas were defenseless during eclosion, so they typically didn't emerge during daylight. It was generally standard for them to emerge from evening into night, when natural predators like ants and bees had ceased activity.
(Well, a cicada this size wouldn't need to worry about ants or bees.)
Eyeing the giant cicada pupa clinging to the trunk, Rei wondered what to do.
The massive hole in the ground and the giant cicada pupa clinging to the tree trunk—seeing these two things together, Rei could clearly understand what had caused the World Tree's illness, the very reason he had been called here.
Cicada larvae grew underground by feeding on sap from tree roots, after all.
(Though I do have questions—like how it managed to reach the World Tree from beneath a barrier.)
It looked like a cicada on the verge of eclosion, but a twenty-meter cicada was impossible under normal circumstances. Rei's conclusion was that it had to be a monster.
(In other words, the World Tree kept losing its magic power and growing weaker because this thing was draining it through the roots. But... what do I do? Killing it in its current state wouldn't be that hard, but doing so would damage the World Tree as well.)
Death Scythe in hand, he agonized over what to do.
The pupa clung firmly to the World Tree's trunk with ten legs, five on each side. The bark had been stripped away, and the tips of those legs pierced deep into the wood.
Not only that—despite being in a pupal state, it was still actively drawing sap from the World Tree through its legs.
Given how firmly it clung to the tree, attacking the pupa recklessly would certainly cause collateral damage to the World Tree.
(The biggest problem here is the World Tree itself.)
Rei's gaze shifted to the World Tree, then to the Light Sphere floating right beside him.
Its flickering had grown gradually weaker, and Rei sensed that this reflected the World Tree's decline.
(There's no time, either. The quickest way to attack would be from the inside, but...)
When it came to attacking from within, the first spell that came to mind was Dancing Flame Serpent.
It was a vicious spell that conjured a serpent of flame inside the enemy, burning it from the inside out.
But that serpent was made of fire, and it carried enough power to potentially inflict major damage on the World Tree as well.
A weakened version of the spell might avoid that concern, but then it might not deal enough damage to the twenty-meter pupa.
(Then...)
Rei's gaze shifted to Set, who was nearby, raising a threatening cry toward the giant cicada pupa.
With Power Crush, which had enough force to shatter solid rock, there would be no risk of spreading fire. There wouldn't be, but...
(Those ten legs piercing deep into the World Tree are in the way. If I blow the pupa away carelessly, that force will transmit straight through the legs embedded in the trunk, and there's a high chance it'll cause major damage to the tree. Which means... should I attack right after it emerges?)
He considered it, but even in its current pupal state, the World Tree's leaves were still withering rapidly. If they waited until eclosion, the World Tree would undoubtedly suffer significant damage.
The Light Sphere floating beside Rei flickered intensely, as if screaming hurry up and do something—even as its light grew steadily fainter.
Given that desperation, this was no situation to wait around for the pupa to emerge.
After a moment's thought, Rei realized he was currently positioned directly in front of the pupa as it clung to the World Tree.
"I see. If I can deal even a little damage from the side..."
Fortunately, among his available options, Rei had a spear he could throw for a pinpoint strike—and more importantly, he had Flying Slash.
With Flying Slash now significantly more powerful than before, there was a chance he could cleave the giant cicada clean in half from the side while it was still in its pupal state.
He couldn't tell exactly what was inside the pupa at this stage, but if things went well, he might be able to dispose of the giant cicada in one fell swoop before it reached adulthood.
Making that call, Rei brought Set and the Light Sphere around to the side of the World Tree—to a position where he could target the pupa from a direct lateral angle.
"Good thing it can't move while it's in its pupal state."
"Gururu!"
Set barked in response, and the Light Sphere flickered to convey its own agreement.
From somewhere far off, the faint voices of the Dark Elves locked in battle could still be heard, but there was nothing to be done about that right now.
The only thing Rei could do was kill the giant cicada as quickly as possible and rush to reinforce them.
"Phew... alright."
After a short, deep breath, Rei held a spear retrieved from the Misty Ring in his hand.
He had hesitated briefly over whether to use Flying Slash or a spear throw, but ultimately chose the spear—a more precise single strike.
"Set, I'm counting on you for backup if anything happens."
"Guruh!"
Set rumbled from his throat as if to say leave it to me.
Trusting him, Rei stroked Set's head with his free hand, then turned a sharp gaze toward the pupa.
He firmly felt the grip of the spear shaft in his hand, then added a twist to his body with a few running steps and hurled it with everything he had.
The spear tore through the air, flying at a speed that would be impossible for an ordinary person to track with their eyes.
Just as Rei intended, it sailed toward what could be called the flank of the pupa—but the moment it closed to within about three meters, it was deflected away as if striking an invisible wall.
"...What?"
Rei muttered, still in his throwing stance. But he had seen and understood exactly what had happened.
His attack had been blocked by some kind of barrier.
"A Protective Barrier? ...Well, it grew up feeding on the World Tree's sap, so it wouldn't be strange for it to use a barrier similar to the World Tree's. But one strong enough to block my attack?"
Even as the doubts swirled, seeing the Light Sphere flickering more intensely than ever told Rei that the World Tree was almost out of time.
He decided to think later. Taking down the pupa came first. From the Misty Ring, he drew not another spear, but Death Scythe.
Fortunately, through the string of battles in the forest the previous night, he had used Flying Slash enough times to handle it with some proficiency.
It wasn't perfect yet—merely serviceable at best.
But given that the pupa had something like a Protective Barrier, Flying Slash was the best option for a ranged attack, even if it carried some risk.
(If this doesn't work, I'll have to abandon ranged attacks and go in for melee... but since I don't know what other abilities it has, I'd really prefer to deal damage from a distance. Come on.)
Pouring his resolve into Death Scythe, he assumed his stance and swung down.
"Flying Slash!"
The flying slash launched with those words shot straight toward the giant cicada.
It was on a trajectory that would miss the World Tree entirely but land squarely on the giant cicada.
Rei watched, thinking the enhanced Flying Slash might just do it—but in the next instant, the same barrier that had blocked the spear throw materialized and stopped it cold.
"You've got to be kidding me."
He had entertained the possibility that it might be blocked, but he'd still believed the Flying Slash would punch through.
Instead, the Protective Barrier caught it without fail, and the pupa emerged completely unscathed.
"Even if it's using a Protective Barrier, isn't this way too hard?"
"Gurururu..."
Set rumbled in agreement.
The Protective Barrier enveloping the Dark Elf settlement had seemed hard enough that Rei could break through it if he pushed himself a little. With the Flying Slash he had just unleashed, it wouldn't be instant—but he felt that firing off several would probably do the trick.
That was why he couldn't understand how the same apparent Protective Barrier ability could shut him down so completely.
"Could it be that the giant cicada can use the Protective Barrier more skillfully than the World Tree itself?"
The moment he said it, the Light Sphere floating beside him flickered more intensely than ever before—almost as if it were protesting.
Rei had absolutely no way of knowing this, but the reason the giant cicada monster had grown so powerful was because of Rei's own magic power.
The creature, which had been stealing nutrients—sap and magic power—from the World Tree through its roots, had absorbed the very magic power Rei had poured into the tree. That was what had allowed it to become such a formidable entity.
Put simply, without Rei's magic power, it would never have gained this level of strength.
But Rei, completely oblivious to the Light Sphere's reaction, was focused solely on destroying the creature while he still could.
Not that there was anything resembling despair on his face. It was highly unfortunate that ranged attacks hadn't worked, but that didn't mean he was out of options.
"I wanted to avoid close combat if I could help it."
The words slipped out as he gripped Death Scythe.
Given that the thing had an ability like the Protective Barrier, his honest preference would have been to finish it from a distance. Even so, the fact that he still had a way forward meant this wasn't a desperate situation—not yet.
"...You stay back. Things might get dangerous from here."
At Rei's words, the Light Sphere flickered a few times, then drifted away.
Watching it go, Rei turned his gaze to Set.
"Set, sorry—but I'll need you with me on this."
"Gururu, guru, gururururu!"
Set shook his head in response.
Rei could roughly guess what that meant. If close combat was unavoidable, Set was saying he'd take Rei's place.
Like Rei's Flying Slash, Set's Power Crush packed tremendous power. In terms of skill level, Flying Slash hadn't yet reached Level 5, where it would become notably stronger. But thanks to Set's own physical abilities combined with the effect of the Magic Item known as the Bracelet of Herculean Strength, Set actually surpassed Rei's Flying Slash in pure destructive force.
Of course, Flying Slash was a ranged projectile attack, so in terms of a single strike's raw destructive power, it wasn't quite on the same level.
"No. I'll do it."
"Gururu..."
At Rei's firm refusal, Set rumbled sadly and stared up at him with round eyes.
"..."
Several seconds passed under that gaze. Eventually, Rei sighed and spoke while stroking Set's head.
"Fine, fine. You attack after me. I'm counting on you for the follow-up strike."
"Guru!"
Unable to resist those eyes—and judging that wasting time here would be pointless—Rei had compromised. Set rumbled happily at the arrangement.
"Alright, let's go!"
"Gururururu!"
Set let out a brave cry in response.
Rei kicked off the ground, and Set charged after him.
"Uoooooooooooh!"
The pupa loomed larger as Rei closed the distance in a dead sprint. Without slowing, he activated the Sleipnir boots, running one step, then two upward through the air.
Magic power already flowed into the gripped Death Scythe, fully primed to deliver a strike backed by its monstrous sharpness and crushing weight.
But the moment he saw the rapidly approaching pupa up close, Rei caught sight of something—a small crack, like a fissure, running along the creature's back.
(Tch—no matter how you look at it, that's way too fast!)
It was already preparing to molt. He clicked his tongue inwardly, but there was no stopping now. Rei swung Death Scythe down toward the pupa with everything he had.