At first, the Crystal Dragon didn't understand what had happened.
Drawn by the scent of its favorite food, a Worm, it had come all the way here, only to find the Worm's severed head lying on the ground.
For the Crystal Dragon, the Worm was its absolute favorite treat.
It wasn't a food necessary for survival, but rather a purely recreational delicacy.
Having found such a treat, it was only natural to focus on consuming it.
Of course, the Crystal Dragon had noticed Rei and Set nearby.
But they were no threat, and more importantly, they had offered up the Worm's head to it. It had no intention of going out of its way to kill them.
To be precise, even if it were to kill and eat Rei and Set, doing so after the Worm would have felt incredibly bland by comparison.
It had ignored them, thinking that killing such small prey was more trouble than it was worth—until, in the midst of that, the Crystal Dragon suddenly felt a searing pain.
"GOAAAAAAAAAAAAAAAAAAAAA!"
It was less a scream of agony and more a roar born of sheer indignation—an expression of its inability to forgive whatever had dared to inflict pain upon it.
Had any ordinary monster heard it, the roar would have produced an effect even more powerful than Set's King's Intimidation.
It was a tremendously fearsome roar, but Rei endured it.
He had already resolved to challenge the Crystal Dragon—an S-Rank Monster.
Knowing this, he had expected some kind of reaction the moment he attacked, and he had fully anticipated the possibility of a ferocious counterattack.
That was why, even as the roar washed over him, Rei shouted while launching his next strike.
"Next!"
Death Scythe met some resistance, but it still managed to slash through the Crystal Dragon's armor—or rather, its skin. But since it was made of crystal, Rei could only perceive it as armor.
In other words, Death Scythe's attacks were effective.
With that established, what Rei wanted to know next was whether his other weapon—the Twilight Spear—could also get through.
Just like with Death Scythe... though unlike Death Scythe, it couldn't endure as much of Rei's mana. He channeled mana within the limits the Twilight Spear could withstand and thrust it at the Crystal Dragon's armor.
There was formidable resistance, but the spearhead still pierced completely through, burying the Twilight Spear halfway into the Crystal Dragon's body.
(It's hard!)
Gritting his teeth, Rei wrenched the Twilight Spear free from the Crystal Dragon's body with all his strength.
The two attacks revealed that both Death Scythe and the Twilight Spear could deal damage. Death Scythe aside, the Twilight Spear required considerable force to inflict any real harm.
"GOAAAAAAAAAH!"
Perhaps it wasn't just the strike from Death Scythe, but the thrust from the Twilight Spear as well that the Crystal Dragon found intolerable.
It swung its tail—also made of crystal—toward Rei.
An ordinary monster's tail was mostly a whip-like strike.
The Crystal Dragon's tail, covered in crystal, evoked the image of nunchaku... no, weapons like a three-section staff or a nine-section chain whip.
And it wasn't a human swinging that tail—it was a Dragon.
If it landed, even with the Dragon Robe, Rei wouldn't escape unscathed.
If it had been a blade-like strike, the Dragon Robe could have blocked it.
But a blow resembling a three-section staff or nine-section chain whip would naturally not be a slash, but a bludgeoning impact.
For Rei wearing the Dragon Robe, that kind of attack was the most troublesome to deal with.
"But you see!"
He read the trajectory of the tail in advance, deliberately buckled his knees to lower his center of gravity and throw off his balance... then slammed the hand holding Death Scythe against the ground, using the recoil to leap sideways.
The next instant, the tail strike that should have been swung horizontally somehow bent at a right angle and slammed into the ground.
If Rei had remained crouched, the tail would have undoubtedly hit him.
"If it doesn't hit, no attack matters, no matter how powerful!"
He landed from the recoil-fueled leap and swung Death Scythe in the same fluid motion.
He let the handle slide slightly in his grip, closing the gap in distance, and slashed at the tail.
Because it was such a hasty attack, the damage dealt to the Crystal Dragon was by no means significant.
Still, being able to chip away even slightly at the Crystal Dragon's armor was a commendable result for Rei.
"Troublesome!"
Creating distance from the Crystal Dragon, Rei shouted in irritation.
The reason was simple: the tail armor that had just been damaged by Death Scythe's blade was already recovering... no, given that it was crystal armor, "regenerating" might be the more accurate term. Regardless, the wound was vanishing before his eyes.
- Troublesome.*
Thinking that, Rei casually directed his gaze to the wounds he had inflicted earlier with Death Scythe and the Twilight Spear... and a question came to mind.
The wounds that remained there showed no signs of recovery.
Or perhaps they were healing to some slight degree, but unlike the tail, it couldn't be confirmed from the outside.
(What's going on? Well, at least it's clear that its regeneration is significantly inferior to the Dark World Tree's. That's a relief for me.)
The Dark World Tree had possessed an extremely high regeneration ability, but they had still managed to defeat it because it was rooted in the ground as a plant and couldn't move from that spot.
Of course, it had attack methods like swinging its vines and launching its fruit, so it wasn't that nothing moved at all. But being rooted meant it couldn't freely roam the ground.
For Rei and Set, it was precisely because their opponent had been like that, they'd been able to defeat it despite its fearsome regeneration.
If an existence that could definitively be called an S-Rank Monster—like this Crystal Dragon—possessed the same regeneration ability as the Dark World Tree, they would have had no choice but to give up on defeating it.
"GOAAAAAAAAAAA!"
Perhaps understanding that its tail attack had missed, the Crystal Dragon turned toward Rei and opened its mouth wide...
"!? Set!"
Rei called out to Set, who was hovering a short distance away.
From that alone, Set seemed to understand what Rei meant. After a few running steps, it swiftly took to the sky, and Rei leapt onto its back.
The instant Set took flight, a Breath erupted from the Crystal Dragon's mouth.
From atop Set's back, Rei watched the Breath tear through the air.
The trees in its path were encased in crystal the moment the Breath touched them, as if they'd been frozen in ice.
(Crystal Breath, huh. Considering it's a Crystal Dragon firing it, that makes sense.)
Set also possessed the skill Crystal Breath.
It was a skill obtained from the magic stone of a monster they had previously defeated that used Crystal Breath in the same way. Its effect was identical to what the Crystal Dragon had just demonstrated... though its power was overwhelmingly inferior.
After all, Set's Crystal Breath was still only Level 1, so that was only natural.
Rare skills were, by their very nature, usable by few. That was precisely what made them rare.
Because of that, leveling up a rare skill after acquiring it was difficult.
For example, Set's Magic Eye of Shock and Magic Reflection, or Death Scythe's Magic Shield, were typical cases.
Of course, there were rare skills that had reached high levels, like Set's Optical Camouflage or Death Scythe's Terrain Manipulation.
In the case of Terrain Manipulation, for some reason its level had risen even from destroying a dungeon core, so it didn't quite fit into that category.
"Hey, wait, you've got to be kidding me!?"
Rei had been watching the effects of the Crystal Breath from atop Set's back as they flew through the sky, but in the next instant, the crystal-covered trees shattered to pieces.
"Pulverized" would be a more accurate description than "shattered."
Set's Crystal Breath could by no means accomplish anything like that.
Or perhaps, if it reached Level 5—where skills were dramatically strengthened—it might be able to pull off something similar.
"Whoa, this is bad! Set!"
"GRRRRRRRWL!"
The Crystal Dragon likely noticed that Rei and Set were outside the effective range of its Crystal Breath.
Swinging its head wide while continuing to unleash the Breath, it tried to redirect the Crystal Breath toward Set as it flew through the sky.
"Magic Shield!"
At Rei's words, a shield of light appeared.
Set was currently evading the Crystal Breath with its speed, but there was no telling what would happen next.
"GRRRRRRRWL!"
Seeing Rei cast Magic Shield, Set also activated Magic Reflection, generating a light shield similar to Magic Shield's... though considerably smaller.
But for Set, this was likely nothing more than small comfort.
That was because Magic Reflection was, as the name suggested, a skill that reflected magic.
The skill could only reflect magic. When considering whether it could reflect the Breath the Crystal Dragon was unleashing... the odds weren't good.
Having seen the trees encased in crystal and then pulverized, Rei had no desire to test whether Magic Reflection could deflect the Crystal Breath.
"Don't... look over here!"
The Crystal Breath fired into the sky, tracing Set's flight trajectory.
Toward the Crystal Dragon's head, Rei hurled the Twilight Spear with a mix of desperation and irritation.
Since the Twilight Spear had been charged with mana near its absolute limit, the thrown spear pierced into the Crystal Dragon's head, and the impact succeeded in deflecting the Crystal Breath off course.
"GGAAAAAAAAAAAAAAAAAAAAA!"
Naturally, the Crystal Dragon was not amused at being subjected to such an attack.
How dare it do such a thing to me, one of the apex predators of this Forest of Magic.
It roared with such fury.
But both Rei and Set had already grown somewhat accustomed to the Crystal Dragon's roars.
Even hearing it, the roar no longer hindered their movements.
"It worked for now, but... still, I can't shatter or completely pierce through it."
Despite charging the spear to its limit with mana, that was the result. Acknowledging the sheer strength of the Crystal Dragon, Rei recalled the Twilight Spear to his hand.
Perhaps noticing that the Twilight Spear that had suddenly pierced its head had vanished, the Crystal Dragon looked around in brief confusion.
Then, upon seeing the Twilight Spear gripped in Rei's hand—the same spear that had been embedded in its head—the hostility and killing intent emanating from the Crystal Dragon intensified severalfold.
"As I thought, minor wounds heal, but damage above a certain threshold doesn't."
Ignoring the Crystal Dragon's fury, Rei calmly observed his opponent.
The wounds from the initial attack were the same. Even if the visible exterior hadn't recovered, there was a possibility it was healing from the inside.
Still, it was undeniably and overwhelmingly inferior to the regeneration ability the Dark World Tree had possessed. In that sense, it was without question an easier opponent to fight.
"Set, what you need to watch out for most is the Breath. That Crystal Breath is vicious—we absolutely cannot let it hit us. Also, strikes from its limbs, and... I don't know if it can use it, but be absolutely careful of Dragon Language Magic."
Dragon Language Magic.
As the name suggested, it was magic that only Dragons could use.
...In reality, Elena, who had inherited an Ancient Dragon's magic stone, could also use Dragon Language Magic in the same way.
There were also said to be those among Dragon-worshippers who could use Dragon Language Magic. But unfortunately, Rei had never met such a person, so he couldn't verify the truth of it.
For Rei, there was also the sentiment that the Holy Light Religion was more than enough religion for him.
What Rei was most wary of was, in fact, this Dragon Language Magic.
The biggest reason for his caution was that while he knew Dragon Language Magic existed, he didn't know what specific spells it entailed.
He knew the effects of several Dragon Language Magic spells that Elena could use, but if this Crystal Dragon could use Dragon Language Magic, there was no guarantee its spells would be the same as Elena's.
With these thoughts in mind, Rei remained vigilant of the Crystal Dragon's movements alongside Set.