"Boom!"
From the greatest of the explosions, black seawater erupted like a geyser, as though it could pierce the heavens.
Not a single one of the light-trails born of Rozen's talismans struck their targets. Every blast was dodged at incredible speed by those two agile, shadow-like figures.
"Hahahahaha!"
The blackened Ushiwakamaru laughed wantonly, as if reveling in the dance upon the edge of a blade—utterly unlike the girl of the past.
"So this is the strength of humanity's final Master?"
The blackened Okita, in stark contrast to her usual brightness and cheer, had become cold and merciless. She muttered without emotion, regarding no one else as living beings at all.
Amid the blasts, the two corrupted Servants retreated swiftly, withdrawing once more to Kingu's side.
By then, Kingu had already completed his task.
The golden urn had merged into Tiamat's body, causing dreadful torrents of mana to surge within her.
By its power, the Black Sea swelled ever more violently. Its mud boiled like magma, flames rising as the corrupted waters heaved.
And from within that Black Sea, the Laḫmu began to change.
Roman had once explained that the Laḫmu born thus far were but juveniles—that they would later evolve.
Now that prophecy was fulfilled.
Each Laḫmu emerging from the sea warped and twisted, their claws growing sharper, their bodies more complex, sprouting a pair of wings upon their backs.
Yes—the Laḫmu had grown wings.
"Qkde qkde! G@'fffffffffffffff!"
"Qkde qkde! G@'fffffffffffffff!"
"Ahahahaha!"
"Ahahahaha!"
Amid their loathsome cries and mad laughter, the Laḫmu completed their growth and took to the skies.
"Damn it!"
Ishtar's face darkened at the sight.
Rozen, however, grew calm.
Realizing the situation had passed the point of no return, he forced himself to cool his mind—colder, colder still.
And then—
"The time has come!"
Kingu turned, arms spread wide as though commanding both the countless Laḫmu and the two blackened knights at his side, his voice rising in proclamation.
"To raise the wandering Gorgon as a goddess, to set her against Quetzalcoatl—drawn by the chain-summon—and against Ereshkigal—called forth by Uruk's priestess—thus balancing one another, restraining the King of Uruk's hand, waiting for Mother's return… and then offering the Holy Grail to her, to shatter her final seal! The plan ends in perfection!"
"Now, by Mother's will, we shall scour this earth, annihilate mankind, supplant mankind, and as the new humanity, inherit this planet's history!"
"The 'Alliance of the Three Goddesses' is already ash and smoke. What remains is only Mother, the Goddess of Creation; the Laḫmu, who shall become the new humanity; and Tiamat's children—Kingu, Ushiwakamaru, and Okita Soji!"
"Here we the three children of god! As the offspring of Tiamat, we shall aid the Goddess of Creation in shaping a new world!"
"Now—reveal your true form, O Tiamat!"
As those words fell, the radiance of the Holy Grail blazed upon Tiamat's body.
The light of a wish fulfilled.
For at the very last, Kingu had spoken his wish to the Holy Grail—for Tiamat to reveal her true form.
In other words, the seal was broken.
Snap!
One of the binding ropes upon Tiamat's body shattered.
Snap! Snap! Snap! Snap! Snap!
One after another, the cords restraining her burst apart, freeing Tiamat from her shackles.
At last, when every rope had fallen away, Tiamat lowered her head, her arms falling slack.
Then—
Rumble!
The ocean itself convulsed.
Rumble rumble…!
At that instant, all the seas of the era trembled, surging with vast waves.
The Black Sea.
And even the seas yet untouched by its corruption.
BOOOOM—!
At Tiamat's location, the waters erupted like a volcanic explosion, blasting upward into the greatest spray yet seen, forming a towering curtain of water that swallowed her whole.
"…!"
Rozen instinctively tried to rush forward—only for Ishtar to seize him.
"Danger!"
She dragged him away at high speed.
Almost simultaneously, the Black Sea surged, its mud forming colossal waves, black tsunamis that swept outward in every direction—drowning the spot where they had stood a moment before.
Rozen and Ishtar were forced to retreat again and again, two streaks of light chased by the tsunami of blackness—tiny against the overwhelming flood.
"We can't let the mud touch us! Fall back now!"
Ishtar's urgent cry jolted Rozen back to clarity.
Taking a deep breath, he sped with her toward the land of Mesopotamia.
But the black wave was relentless, pursuing them without pause.
In that moment, the Black Sea devoured the ocean at unprecedented speed, turning its waters into its own domain.
"No way!?"
Ishtar gasped in shock.
"Because she obtained the Holy Grail, the Authority's strength has been boosted—the erosion's speeding up!?"
Rozen's expression turned grim.
Then the communicator crackled to life.
"This is bad!"
Roman's panicked voice rang out.
"The Black Sea's water level is rising by the second! It's spreading toward Mesopotamia's land! At this rate, not just the ocean—the very land will be consumed by the mud!"
And what would that mean?
It meant every living thing upon the earth would be swallowed by the Black Sea, burned away by its mud.
"If it reaches the land, humanity's finished! Uruk will fall, human history will collapse! Mesopotamia—the foundation of urban civilization, one of the four great cradles—will be a world of monsters! Human Order itself will perish!"
Roman's cry trembled with fear, and Rozen's face darkened.
And yet—already the land was before him.
At the ocean's end, Mesopotamia stretched forth, and Rozen and Ishtar raced into it.
Inevitably, the tsunami of black mud rushed after them, ready to wash ashore.
Seeing this, Rozen halted mid-flight.
"I won't let you succeed!"
Mana surged from him like a storm.
"Come forth! The first Beast Vassal—Mesarthim Adamas!"
At his roar, his mana became a mist of blood, coalescing into the immaculate form of a diamond ram upon the coast.
Rozen poured every last measure of his mana into it.
The Mesarthim Adamas he summoned reached a size of a thousand meters—like a towering god.
"Block it!"
Rozen channeled all his power into the Beast Vassal.
The diamond ram roared and spread its arms wide.
Vmmm!
With a tremor that shook the very air, a colossal barrier of gem-like brilliance rose up, spanning the entire coastline.
Boom!
The black tsunami struck, crashing against the gem wall, making it shudder violently.
But it held.
The tidal wave of mud was stopped, unable to surge onto the land.
"…Hah…"
Only then did Rozen allow himself a breath of relief.
But then—an anomaly occurred.