"Cu Chulainn!"
Bazett rushed to her fallen servant's side. To her horror, Cu Chulainn's spiritual foundation was rapidly dissolving, leaving him no time to utter a single word. As he vanished, several grotesque insect-like creatures that devoured magical power fell to the ground.
Deprived of their host's magical power supply, the insects quickly withered and died.
"This... Insect Magic!" Bazett realized.
Though unfamiliar with the Three Great Houses of Fuyuki City, she had been observing Shinji Matou's actions for some time. It was impossible for her not to recognize the Matou family's signature magic. Her eyes burned with murderous intent as she glared at Shinji. He must have planted these insects during his battle with Cu Chulainn, taking advantage of the opportunity.
"Heh heh heh, young people are so impatient," Shinji chuckled. "But my magic is a little too distinctive, isn't it?"
He looked up at the Soul Crystal in the sky, clutching his chest as a sharp pain pierced his heart.
"So, even this temporarily enhanced magic circuit couldn't sustain the Holy Grail's form after all?"
"Never mind. It's just a temporary vessel. Time to abandon it! As long as I can open that hole, everything will be fine."
Shinji Matou tore open his chest with a maniacal laugh, and a small insect crawled out of his body.
As the insect departed, Shinji's body began to swell grotesquely. His flesh multiplied uncontrollably, and the return of his own consciousness brought with it an incomprehensible pain that forced tears from his eyes.
"Wh-what's happening? Grandpa, Sakura, help me!"
He instinctively cried out to the familiar Magus for help, but the only one who could aid him now was Zouken Matou, the mastermind behind this horror. Shinji's body couldn't supply the Holy Grail's demands, so his flesh continued to expand relentlessly, growing to tens of meters in height until a towering mass of meat formed.
Fortunately, Shinji's transformation was confined to an isolated area, preventing the grotesque expansion from directly harming the spectators. However, the sheer horror of the twisted spectacle sent waves of terrified screams through the crowd as they desperately tried to flee.
Then, a black void opened above the "high tower," spewing forth a torrent of malicious Black Mud that threatened to engulf the spectator stands.
"Even though Jiang You warned us about this and prepared countermeasures, seeing it in person is still deeply unsettling," Medea muttered.
She maneuvered Shinji Matou's floating platform further away from the crowd. However, the Black Mud, a manifestation of pure malice, began corroding the very fabric of the space, igniting flames in certain areas. Medea struggled to maintain the dimensional barrier; if it collapsed, everyone present, including the servants, would be plunged into the Black Mud.
Sensing an ominous presence within the sludge, Medea dared not gamble on what might happen to a servant immersed in it.
"So this is it? I did sense something peculiar emanating from Shinji Matou earlier, but I assumed it was his fault. Could this actually be the fabricated demon from the Third Holy Grail War?"
Zouken Matou finally confirmed his suspicions about the Holy Grail's corruption. His theory about the Soul Crystal being the primary target had been correct.
"Since the Holy Grail has gone haywire, I'll just take it for myself!" he cackled.
"This is... the Holy Grail. Just as Caster said."
Rin Tohsaka sensed the overwhelming malice emanating from the void. "But even with Lancer defeated, only one Servant has fallen. How can the Holy Grail possibly have enough magical power to manifest?"
"I suspect it's due to the Shadow Game's effects," Sakura Matou replied.
Sakura had witnessed Jiang You transform Zouken Matou into a Soul Crystal. The only Servant she'd seen Jiang You defeat using the Shadow Game was Gilgamesh, and Medusa had been present during that battle, yet no Soul Crystal had been produced. The souls of Servants must also be influenced by their Noble Phantasms.
The chaotic scene provided Zouken Matou with an opening. Fueled by magical power, he surged toward the Soul Crystal.
He understood the profound utility of the Third Magic's crystal. As one of the Three Great Houses that constructed the Holy Grail, his knowledge of this artifact rivaled even that of the Einzbern family. Unlike the Einzberns, who sought to replicate the Third Magic itself, Zouken merely desired to extract the power of immortality from it. Given a few more years, he could finally realize his long-cherished wish.
"The Soul Crystal... it's mine!"
Zouken Matou realized the organizers hadn't taken the Soul Crystal seriously. The Duel arena was almost entirely devoid of defensive spells, giving him the perfect opportunity to strike.
Just as he was about to use magic to escape with the Soul Crystal, it vanished into thin air.
Left without a foothold, he plummeted to the ground.
"How is this possible?"
Zouken couldn't detect even a trace of magic, as if the Soul Crystal had simply ceased to exist.
"Nothing is impossible. Anything that belongs to me remains mine until I choose to give it away."
Suddenly, Zouken was struck by a powerful blow. Jiang You's kick sent him flying against the wall. Items like this were meant for Duelists to store in their inventories at will. The protective array around the Soul Crystal had merely been meant to prevent theft while Jiang You was absent, proving to everyone that the organizers had the real thing.
"You... how are you here?"
In this Worldline, Zouken didn't recognize Jiang You. But he knew that a servant capable of casually wielding a Soul Crystal as a plaything was no ordinary opponent.
"Weren't you still in the Duel?"
"I suspected something like this would happen—I knew someone wouldn't play fair!"
Even in the original Yu-Gi-Oh! series, people cheated by bypassing the cards, so it was hardly surprising that the Type-Moon World would be even more prone to such schemes.
"Take another look at the Duelists on the field."
With the sudden crisis, Serenity abandoned her disguise. Across from her, Illya tore off her own facade, revealing black armor—Lancelot himself. Under Hundred Faces' direction, all the Heroic Spirits began assisting with the evacuation of the crowd.
"Didn't I tell you, Illya?"
Jiang You extended his hand to his side. Illya emerged from behind him, glancing at him with slight hesitation before taking his hand.
Jiang You seized the opportunity, sweeping her into his arms. He supported her thighs with one hand, cradling her against his bicep.
He held her in the same manner Hercules had once carried him, a feat easily accomplished with Jiang You's current strength. However, lacking Hercules' physique, Illya had to wrap her arms around Jiang You's neck to maintain her balance.
"Heh heh heh... colluding with the champion to cheat? Looks like the fix was in from the start, wasn't it? You organizers are nothing but hypocrites."
Zouken Matou chuckled. "Since you've discovered my true nature, go ahead and kill this old man. In this form, your Noble Phantasms are useless against me. All it would take is a gentle kick..."
Jiang You knew the Old Man Worm had other escape routes, so he initiated his own Shadow Game. "Worms are notoriously difficult to kill, so—let's play a Shadow Game!"