At that very moment, in one corner of Itogami Island—which had become a battlefield overrun by countless monsters and Beast Vassals—the most terrifying upheaval occurred.
"Boom!"
With a thunderous roar, that section of the sky and earth was instantly transformed into a frozen wasteland where a raging blizzard howled. The frost filled the skies, obscuring the sun and heavens, creating a terrifying spectacle.
At the heart of this wintry domain stood a Beast Vassal, clear and crystalline like a frozen river.
It was a creature over ten meters long, with the upper body of a woman and the lower body of a fish, wings extending from her back, and talons like those of a raptor at her fingertips—an entity resembling a mermaid of ice, or perhaps an avian ice demon.
This was the Twelfth Beast Vassal of the Fourth Primogenitor, the embodiment of frost and snow—Alrescha Glacies.
Summoned by Avrora, this Beast Vassal appeared and, with a wave of her hand, instantly froze countless Beast Vassals in the snow, causing them to shatter like ice shards and scatter across the land.
Avrora directed Alrescha Glacies to challenge the oncoming wave of Beast Vassals summoned from the Rose—those controlled by December or rampaging in a berserk state—scattering them one by one.
Meanwhile, Himeragi Yukina had entered into a fierce battle with Senga Takehito, but unlike Avrora, her side was at a clear disadvantage.
Because Senga Takehito was one of the most powerful Onmyoudou practitioners of the modern era, capable of overcoming armies on his own, defeating a mere Sword Shaman apprentice of the Lion King Agency was no difficult feat.
Even with the power of the Mechanical Demon-Purging Assault Spear Mark Seven, Yukina found it of limited use against Takehito.
After all, Takehito was neither a Demon nor a typical mage. The Kimon arts he used involved both spiritual power and mana, and he could switch between them depending on the situation.
Thus, even though the Assault Spear could nullify mana, it was ineffective against spiritual power.
As a result, against a master like Takehito, Yukina naturally found herself in a bitter struggle. If not for her ability of Spirit Vision, which let her foresee several seconds into the future and evade attacks, she likely would have already lost.
To avoid defeat, Yukina desperately poured spiritual energy into Sekkaro, which then converted it to divine energy. This, accompanied by the glow of a divine harmonic wave, lit up the battlefield. With a shout, Yukina launched a relentless attack on Takehito.
Though he managed to fend off Yukina's offensive, for the moment Takehito was unable to disengage and aid December.
Under these circumstances, December fell into danger.
"Come forth! The Ninth Beast Vassal—Alnasl Minium!"
Rozen summoned the crimson-maned dual-horned warhorse, which charged forward engulfed in wind and vibration waves, as though dominating the very air itself, thundering toward December.
"Stand down! No. 9!"
December shouted at the warhorse, while behind her, the crystalline dragon released waves of invisible mana in an attempt to mentally control Rozen's Beast Vassal.
"Crush her!"
But Rozen ignored the psychic assault and issued a cold command.
The crimson dual-horned warhorse let out a sky-piercing neigh, scattering the psychic wave and charging directly at December. Its front legs came crashing down like divine pillars.
The impact, heavy as a mountain, caused the very atmosphere to scream and made the artificial island quake.
The targeted December had her clothes rippling violently as if struck by a gale. Her face twisted in anguish, and her eyes filled with sorrow and resignation.
"I never imagined… you would submit to him to such a degree… my brethren."
As one of the same kind, December could sense it clearly—even though Rozen's control over the Beast Vassals was absurdly powerful, even beyond that of the Fourth Primogenitor, what was truly astonishing was how much the Beast Vassals acknowledged and obeyed him.
This was a deeply inexplicable phenomenon.
Beast Vassals had their own wills, and they were notoriously powerful. The stronger the Beast Vassal, the more arrogant it became. Even Primogenitors couldn't easily earn their recognition—hence the existence of vampires incapable of summoning their Beast Vassals at all.
Normally, a Beast Vassal might acknowledge a host and lend its power, but absolute obedience was another matter—even Primogenitors couldn't achieve that.
That's why only Vatler had ever been able to fuse Beast Vassals in the past. It required not only perfect mana control but also complete domination over the Beast Vassals' will.
Vatler managed this not by force but by aligning with their ideals. His nine Beast Vassals respected him for rising to a level close to the Primogenitors as a mere pureblood vampire and voluntarily submitted to his fusion command.
In other words, to unilaterally dominate a Beast Vassal was practically impossible. The stronger the Beast Vassal, the more impossible it became—unless it willingly accepted the host.
And yet, Rozen had done it. Not only could he fully control their power and will, but even the strongest ten Beast Vassals in the world submitted utterly to him—as if choosing obedience of their own volition in response to his strength and presence.
Thus, December's attempts to control her fellow Beast Vassals were no more than pipe dreams.
She couldn't even influence the Beast Vassals Rozen summoned through those door-like magic circles—not a single one.
"Minamiya Nichiyo!"
December finally began to understand how this human could seal the Divine Child of Origin, and even call the God of Sin back into this world.
Because he was terrifyingly powerful.
All the Beast Vassals bowed their heads to him.
December hastily deployed Dabih Kryastalos in front of herself, raising her crystal pillar-like horn to clash against Alnasl Minium's descending forelegs.
"BOOM!!!"
The collision of Primogenitor-class Beast Vassals released terrifying magical energies that clashed and erupted into shockwaves.
The ground shattered instantly.
The air warped and exploded.
Even a nearby gas station, struck as if by a level-15 typhoon, was blown apart like a toy—reduced to ruin.
The result of this clash: Alnasl Minium's overwhelming victory.
Lacking raw destructive force, Dabih Kryastalos was completely shattered under Alnasl Minium's stomp.
"Aaaaarrrggghhh...!"
December let out a pained scream as the shockwave blasted her away, sending her crashing to the ground and rolling for meters.
Blood flowed from her body.
"December!"
Senga Takehito shouted and tried to rush over—but failed.
"Haaaahhh...!"
Yukina, glowing brighter than ever with divine harmonic wave light, surged with divine energy and charged at Takehito.
Her speed was vastly higher than before.
"Shing!"
Her silver spear slashed down.
"Splurt!"
Caught off guard, Takehito was struck hard in the chest.
"Gah...aah...!"
He let out a cry of pain and collapsed to the ground.
"Hah... hah... hah..."
Yukina stood there panting, divine energy still glowing from her body, a halo forming faintly behind her.
She looked just like an angel.