There was no denying it—the horned serpent transformed by the Knight of the Sinful God was indeed a threat.
The foreign erosion ensured it was completely immune to supernatural attacks and influences.
By absorbing and assimilating the data of the other Knights of the Sinful God, their cursed artifacts, wyverns, and even mechanical puppets, the horned serpent had gained extraordinary physical attributes. Even direct physical attacks could only deal limited damage to it.
Rozen, at his core, was still a magus and jujutsu-user. Though he no longer had the weakness of being poor at close combat, facing such a massive monster and trying to defeat it through brute force alone wouldn't be easy.
Moreover, since Beast Vassals were essentially condensed masses of magical energy, they would be nullified by the foreign erosion. Dealing with this creature would indeed require considerable effort from Rozen.
At least, under normal circumstances.
"Do you need me to intervene?"
The voice of Artoria [Alter] echoed in Rozen's mind.
"Senpai."
Mash's serious and resolute tone followed.
"Poison is effective against it. Please allow me to fight, Rozen-sama."
Serenity also made her request.
Only Jeanne [Alter] remained silent, though Rozen could faintly sense her frustration. She probably understood that the foreign erosion countered her abilities. While she wasn't completely helpless, she was at a disadvantage compared to the other three.
Indeed, if Mash and the others were to join the battle, dealing with the horned serpent wouldn't be an issue.
But—
"Even for you, without the ability to use magical attacks, hacking away at this thing bit by bit would still take time."
Rozen smirked and spoke decisively.
"I'll handle it."
He already knew how to counter the foreign erosion.
And so—
"Come forth!"
Rozen's magical energy erupted, transforming into a crimson mist.
"Cor Tauri Succinum!"
The ground beneath them suddenly turned molten red, as if a volcano had awakened. Then, with a thunderous roar, the earth split open, and a colossal Minotaur God wielding a blazing battle-axe emerged—its entire body forged from searing magma.
"ROOOOAR—!"
The Minotaur let out a deafening bellow and charged straight at the horned serpent, raising its axe high before delivering a devastating downward slash.
"Fool!"
The horned serpent roared in both fury and mockery.
"Beast Vassals are useless against us, the Knights of the Sinful God!"
As it charged, a dark aurora swirled around its body—the Foreign World Erosion, capable of repelling all supernatural forces. Even the calamity-level Beast Vassals of the Primogenitors, or the twelve legendary Beast Vassals of the Fourth Primogenitor, would be powerless before it.
But in the very next second, the serpent's confidence shattered.
"BOOM—!"
With an earth-shaking impact, the molten battle-axe of the Minotaur God pierced straight through the black aurora and sent the horned serpent flying.
"GAAAAAH—!"
The creature howled in agony as it crashed into the ground, rolling violently and flattening countless trees in its path, leaving a massive trench in its wake.
Unlike other Beast Vassals, this attack didn't rely on overwhelming destructive force. Instead, it exhibited sheer physical power, shattering a portion of the serpent's armored shell.
"Impossible!!"
The horned serpent was stunned.
And it wasn't the only one. Even Vatler and Iblisveil, watching from a distance, were momentarily taken aback.
As vampires—top-tier beings second only to the Three Primogenitors, far surpassing ordinary Second-Generation royalty—they were intimately familiar with the nature of Beast Vassals. Thus, they immediately realized what had happened.
"That's… the second beast vassal?!" Iblisveil muttered in disbelief. "He fully materialized it?!"
Yes.
Fully materialized.
Rozen had summoned Cor Tauri Succinum not as a Beast Vassal, but as a Familiar—a completely physical entity.
This was something he had done before.
Both Familiars and Beast Vassals were essentially sentient masses of condensed magical energy.
But just as humans, at their core, are merely concentrations of life force yet still possess flesh and blood, Servants—despite being constructs of magical energy—can bleed, cry, and even eat or drink because their energy is fully materialized into tangible form.
Rozen's Familiars had always been fully materialized. They could bleed, feel pain, and even reproduce if their species allowed it.
Beast Vassals, however, were only semi-materialized. While they had form, their interiors remained dense concentrations of magical energy.
This was why Beast Vassals had low endurance and high consumption—summoning them required vast amounts of energy, and if faced with stronger magical attacks, they could be overwhelmed. Their advantage lay in their explosive destructive power, capable of leveling cities with ease, and their immunity to physical attacks.
Familiars, on the other hand, lacked such overwhelming force but were far more efficient—requiring less energy, capable of sustained combat, and easier to deploy in coordination.
If Beast Vassals were bombs, missiles, or even nukes, then Familiars were tanks, fighter jets, and aircraft carriers.
The foreign erosion could nullify all supernatural forces, including semi-materialized Beast Vassals.
But against fully materialized Familiars—physical entities whose attacks operated within the laws of physics—it was powerless.
Unless those Familiars used magical attacks, the erosion couldn't stop them.
And so, this time, Rozen hadn't summoned Cor Tauri Succinum as a Beast Vassal—but as a Familiar.
What stood before the horned serpent now was not the Fourth Primogenitor's Beast Vassal, but a fully materialized Minotaur God.
Which meant—
"I could drown you in sheer numbers, you heretic."
Rozen declared coldly as his magical energy surged once more.
"Al Meissa Mercury!"
A twin-headed dragon, its scales gleaming like liquid mercury, materialized in the sky.
"ROAR—!"
"ROAR—!"
Both heads roared in unison as the colossal dragon slammed down onto the struggling horned serpent, pinning it beneath its massive claws.
Then, without hesitation, the twin heads sank their fangs into the serpent's body.
"CRUNCH—!"
The jaws of the dragon, capable of biting through dimensions, tore two massive chunks of flesh from the serpent in an instant.
"AAAAAAAAAAHHHH—!!"
The agonized scream of the Knight of the Sinful God echoed across the battlefield.