Kayneth El-Melloi Archibald's appearance in the Einzbern Forest was no coincidence.
Shortly after Tenkei Shiomi and Morgan had left their home, Kayneth, fully armed with magical implements and formal Magecraft attire, arrived at the Shiomi residence in Miyama Town along with his Servant, Lancer.
A Magus's home was, by definition, a workshop—typically fortified with layers of powerful barriers and riddled with traps meant to deter both fellow Magi and ordinary intruders.
In that regard, Tenkei Shiomi was no exception.
Though the Shiomi residence's barrier gave the illusion of being unguarded, it was in fact a meticulously designed trap. A single misstep in approach would have triggered complications impossible to shake off.
Of course, for someone like Kayneth—Clock Tower's prodigy and heir to a prestigious magical bloodline—it was merely a mild inconvenience.
He effortlessly opened a gap in the barrier and ordered Lancer to search the house, only to find it abandoned.
Kayneth then used a tracking spell to trace Shiomi's trail, which led him all the way to the Einzbern Forest.
His plan was straightforward: pick off Caster first, and then seize the right moment to eliminate Tenkei Shiomi.
But if the latter had already recognized his disadvantage and sought cooperation from another faction—especially one of the three founding families of the Holy Grail War system—then it was a different matter entirely.
On his way into the forest, Kayneth discovered that Caster was already engaged in battle. The rapidly multiplying sea demons had engulfed the battlefield. Even Lancer could see only Saber, her figure flashing in and out among the creatures, while Caster stood at the center, sustaining his Magecraft through the grimoire in his hands.
Yet amid the swarm, Lancer could sense another overwhelming magical presence—one on par with Caster's.
A presence equal to a Servant. Which meant... Berserker was there too.
After their initial encounter the night before, Kayneth had come to understand this Berserker was no ordinary brute, but a rare outlier with spellcasting prowess rivaling top-tier Casters.
He surmised that Saber and Berserker were currently acting on their Masters' orders, temporarily joining forces to take down Caster.
Which made Kayneth's next move obvious.
He instructed Lancer to remain hidden, wait for the right moment, and then dive into the fray—snatching credit for Caster's defeat at the crucial moment.
Command Spells were invaluable strategic assets. Even if his side didn't take any losses, it was essential to prevent other Masters from gaining more.
Lancer found the tactic distasteful—stealing another's glory ran counter to his knightly ideals. But letting Caster continue his atrocities was far worse. So he swallowed his pride, obeyed Kayneth's command, and readied himself to strike down evil as a lone ranger.
With Lancer's mission set, Kayneth moved deeper into the Einzbern Forest and reached the castle grounds.
He had prepared for everything. If it came to a Magecraft duel—even if he were outnumbered two to one or three to one—he was confident he could triumph over any of the Masters, including Tokiomi Tohsaka.
"As expected of a distinguished German Magus lineage," Kayneth scoffed, surveying the estate. "Even in a remote backwater like this corner of the Far East, they still insist on living in a castle."
...Even though, in terms of ancestry alone, the Einzbern line was no less venerable than that of the Archibalds.
Kayneth placed a glass bottle filled with mercury on the ground, its weight pressing the base deep into the earth. He had used Magecraft to lighten the container enough to carry it with him.
Though the bottle appeared no larger than a standard school lab container, it actually held a full 40 kilograms of mercury.
"Fervor, mei sanguis—Boil, my blood."
This was the centerpiece of Kayneth's magical arsenal—his prized Mystic Code, the "Volumen Hydrargyrum."
"Automatoportum defensio:Automatoportum quaerere:Dilectus incrisio."
With each incantation, the mercury spilled across the floor began to tremble faintly, as though beads of high-tension liquid were rolling free from the vessel.
The doors to Einzbern Castle weren't locked; in fact, they stood wide open, saving Kayneth the trouble of breaking in.
He climbed the steps and entered the grand hall.
"I, Kayneth El-Melloi Archibald, ninth head of House Archibald, have come to call! Magus of Einzbern, for the Holy Grail we both seek, let us stake our lives and honor in fair combat!"
Kayneth's voice echoed boldly through the hall.
But the response he'd anticipated never came. No traps sprung. No Magecraft lashed out at him. It was as though the brightly lit castle were deserted.
"How gaudy. In this age where mystery fades, has Magecraft really been reduced to a vulgar tool for chasing hollow fame?"
A cold woman's voice echoed in reply.
With it came the distinct click of high heels descending the stairs.
At the top of the staircase opposite the main entrance, where the hall branched into a split platform, a silver-haired woman gracefully descended, hand resting on the railing. She turned elegantly at the landing.
She wasn't an Einzbern homunculus, but—
"…Berserker…"
Kayneth inhaled sharply. He realized, belatedly, that he'd grown overconfident in his preparations. He'd automatically assumed that the enormous magical energy he'd sensed—on par with a Servant's—belonged to one.
In reality, it had been Tenkei Shiomi, the Master, fighting alongside Saber against Caster.
Kayneth knew he couldn't win against a Servant. But escaping alive? That was still possible.
He began to activate the Volumen Hydrargyrum to retreat—only for the castle doors to slam shut behind him, sealed with a surge of massive magical power.
"Despite what I said earlier," Morgan spoke calmly from the top of the stairs, raising her index finger with a faint, amused smile, "since you've come here challenging me with your name and honor as a Magus, it would be improper for me not to respond. One minute. If you survive my Magecraft for one minute... I might just let you walk out of here tonight."
After all, it had been Kayneth who ordered Lancer to attack Shiomi.
Just the sight of him stirred Morgan's contempt.
Yet now, she found satisfaction in her role as Shiomi's wife.
If a wife handled everything for him, Shiomi might not find that appealing—so Morgan refrained from issuing a death sentence. Instead, she would let this arrogant man live, just long enough for Shiomi to deal with him personally.
This is bad.
The confidence Kayneth had moments ago vanished. He now understood—his only hope of survival lay in enduring this minute.
"Vollständige Verteidigung—Complete Defense!"
Defense was the only option.
Before Morgan had even finished speaking, he had already steeled himself, waiting in silence for the first attack.
He activated the Volumen Hydrargyrum, its mercury shield rising to meet whatever was coming.