From a strategic standpoint, Amakusa did not want Karna to use "that" Noble Phantasm.
[Vasavi Shakti] , O Sun, Abide to Death.
It was the ultimate God-Slaying spear in Karna's arsenal, an Anti-Divine weapon with a destructive capacity that surpassed even his golden armor's defense.
However, the cost of unleashing this spear was steep: it required Karna to shed his golden armor, permanently losing his [Kavacha and Kundala].
In other words... he had to discard his near-invincible defense to forge a weapon capable of killing a God.
The sheer power of the [God-Slaying Spear] was beyond human imagination. It was conceptual destruction that could erase monsters, phantasmal beasts, divine beings, armies, fortresses, and even the world's laws.
But the price was too high. Once the spear was used, Karna would lose the protection of his golden armor for the remainder of the war, leaving him dangerously exposed.
Since the full capabilities of the Black and White factions remained unknown, Amakusa had determined that this trump card should only be used in a truly desperate situation.
Yet, being pushed this far by the Black Rider alone was an outcome he hadn't prepared for.
'Do not use it.'
Karna studied the enemy before him, reaching the same conclusion after a moment of deep tactical reflection.
Unquestionably, unleashing the God-Slaying Spear would destroy the Uchiha, but with so many unknown variables still on the board, it was a high-risk gambit. If the Black or the as-of-yet unseen White Factions possessed another combatant of Madara's level, they would be at a fatal disadvantage later.
'Then I must ask you to keep the Rider occupied. He likely has no immediate means of breaking your defense either.'
'I will support you with as much magical energy as you need.'
If that was the case, the battle's nature shifted. It was no longer a duel to the death, but a prolonged war of attrition that might last for days.
Amakusa was confident that Karna could endure. Based on the abilities Madara had shown so far, the Uchiha lacked the sheer, concentrated output required to shatter the Golden Armor.
"The Saber who just appeared on the field... is she from the third faction?"
"That radiant Holy Sword... and that legendary scabbard... could it be...?"
After finishing his communication with Karna, Amakusa turned his attention to the new variable. The arrival of a fresh Saber just as their own had been pulled back was a clear indication that the White Faction was finally making its move.
As a man of vast knowledge and history, Amakusa had already deduced the True Name of the newcomer.
The legendary King of Knights from British myth.
Artoria Pendragon.
"It seems she's already engaged with the Black Faction's Caster."
"And there's another presence a short distance from the center of the battlefield."
"The White Faction refused to stay on the sidelines, it seems."
The White Faction's full strength remained a mystery, but for now, Amakusa didn't have the luxury to worry about them.
***
SHOO!
A silhouette blurred through the night, a trail of golden light following it like a comet.
Siegfried remained fully focused, his greatsword sweeping out to intercept several kunai that were thrown from his blind spot.
CLANG!
The kunai were shattered, but Minato appeared on the opposite side, his hand reaching out as if to seize an opening.
Siegfried didn't let him succeed. He yanked his sword back, flooding the blade with magical energy.
CRACKLE!
A shockwave of blue mana erupted, forcing Minato back and preventing any physical contact.
Not one to let an opportunity slip, Minato instantly activated the [Flying Thunder God] seal etched on Siegfried's chest to close the gap again.
FLASH!
But as soon as he appeared in front of the knight's torso, Siegfried was already waiting for him. His free hand swept out, a well-timed grab that caught Minato by surprise.
SWISH!
Minato didn't stay to be captured. He vanished and reappeared several yards away.
"..."
Siegfried stood in silence, his eyes fixed on the elusive blonde man.
TROUBLESOME.
As long as his secret weakness remained hidden, the enemy would continue to probe and strike. But every time Siegfried tried to capitalize on a perceived opening, the opponent was too cautious to commit.
He couldn't touch the man, and he barely had the chance to attack.
For a warrior like Siegfried, dealing with this type of Servant was a grueling exercise in frustration. If this continued, it would end badly. Eventually, purely by the laws of probability, one of the man's attacks would accidentally strike his weak spot.
Minato, too, was maintaining a mask of calm determination.
[Rasengan] to the head hadn't worked. He had intended to use a sealing technique to restrain the knight's movements, but the man was hyper-aware of any close-quarters contact.
That sudden burst of magical energy just now had perfectly countered his attempt to place a binding seal.
Against an opponent with such high passive defense, a standard [Rasengan] simply lacked the necessary "bite."
'I need to find a way...'
'I must find an opening...'
Independently, both Minato and Siegfried reached the same conclusion at the same moment.
***
BOOM!!
SCRAPE!!
The Holy Sword blocked the incoming flaming fist, but even with the reinforcement, Artoria was sent skidding back dozens of meters.
Her boots carved deep grooves into the charred earth as she finally ground to a halt at the edge of a jagged cliff.
The air around them was stagnant with heat, the localized temperature making the valley feel more like a volcanic crater than a forest.
"She's much more troublesome than the last one..."
Natsu watched Artoria, realizing that this woman was significantly stronger than Mordred.
PHEW.
Artoria exhaled, adjusting her breathing as she studied the pink-haired boy.
She was now certain: this was the worst possible matchup for her. If it weren't for [Avalon], she would have found it nearly impossible to contend with a Servant who possessed such potent "Dragon Slayer" characteristics.
The sheer effectiveness of his magic against her "Dragon" nature was preposterous.
'Are all heroes who possess dragon-slaying legends like this?'
She didn't know the boy's True Name. Natsu Dragneel was a name she didn't recognize.
Born of a demon, raised by a dragon, and living as a human... Natsu's complexity was beyond anything Artoria could fathom.
While Siegfried had acquired his "Slayer" trait by killing a dragon, Natsu was different. His magic was fundamentally designed to "slay" dragons from its very inception.
By the laws of this war, if you were a dragon, Natsu's attacks would bypass your logic.
Mordred, despite her legendary armor, had been brought to her knees after only a few punches. Without her scabbard, Artoria would have suffered the same fate.
***
"The situation looks grim."
Red Archer narrowed his eyes as he watched Artoria struggle from his distant vantage point.
The King of Knights, even with her scabbard, was being pressed into a high-stakes duel. It was a scenario he hadn't anticipated.
He didn't know what kind of legend could produce a "fire-breather" of that caliber.
"The battles at the other locations..."
He looked at the field, unsure where to direct his next shot.
On one side, two titanic figures were tearing the world asunder. On the other, a high-speed blur was playing a game of cat-and-mouse with a living fortress.
And then there was Artoria's opponent,a monster who had turned the very earth into a sea of lava.
[Translated and Rewritten by Shika_Kagura]