Shirou Emiya, despite looking almost the same as when Kai had visited the Key Fate Timeline, wasn't the same boy anymore.
In the last year, especially after Kai had sent Tina there, he had been learning more and more about what Kai was and what kind of battles he fought.
Medea had told him about the infinite timelines.
She had also told him about people like Black, who journeyed from timeline to timeline for specific goals.
He learned of Bubbles, Keys, Mirrors, and Pillars; of Deep Ones and Timelines.
More than all that, he learned the significance of their presence in the Multiverse.
It had come as a vast surprise, but, paradoxically, also… normal.
During the Grail War, Shirou had already learned that the Root pulled various Servants from different points in time. So, the concept of timelines within a Bubble had become quite easy to understand. With Archer and Assassin's true identities in mind, he had also gotten a great example to relate this all to.
But these changes were mostly related to knowledge.
Before learning so much about the Multiverse, Shirou had already experienced a qualitative change during the Great Holy Grail War.
Not only had he gained a perfect set of Magic Circuits, but his entire body had also undergone a definite improvement, each strand of his muscles becoming a sword, reflecting his Inner World.
It was these physical and magical changes that had let Shirou match the speed and strength of Black while fighting against the Corrupt Priest — Kirei Kotomine.
It was these changes that had let him survive the onslaught of a Corrupt Divine Servant — Gorgon.
It was these changes that had made him understand the weight of responsibilities that came with them.
So, along with knowledge, Shirou had been training himself to use his abilities more strategically, instead of blindingly charging at the enemy.
Saber was gone, but Rider and Medea were still there, helping him, Rin, and Sakura.
And it was because of all these changes, whether physical or mental, that Shirou hadn't underestimated his opponents.
Looking at the armored giants on the video screens gave an impression that he could punch right through them, especially with the strength he possessed now.
But, while sending him here, into this world — the Harry Potter Mirror — Caster had warned Shirou that he would be facing Pillars, while he himself was barely a Mirror… a delicate one at that.
Medea had told him that their Key timeline had only recently become a Mirror.
With his enemies being Pillars, he wouldn't have stood a chance, no matter how vast his improvements seemed to him.
However, there was one caveat in all this that worked in his favor, Caster had added.
Shirou Emiya was from the Fate Bubble — one of the strongest Bubbles in the Multiverse.
In contrast, the Pillars he would be contending against were from a lesser Bubble; an injured Bubble, besides.
That meant as long as he played his cards right, Shirou stood a great chance of dealing with the enemies whom Black, for some reason, couldn't handle by himself.
Not to mention, he had learned the way these armored soldiers fought through the several video screens showing them slaughtering the people and creatures of this world.
Then there was the presence of the unknown woman.
Shirou didn't know her, but he knew Medea, the Caster.
He had fought against her during the Great Holy Grail War, fought alongside her near the War's end against All The Evil, and then, later, studied under her.
So, despite not knowing the Witch, Shirou did know Witches.
Black had gone as far as to tell him before leaving a year ago that if it hadn't been for Medea, they would have never won against Angra Mainyu.
And it was exactly because of that, knowing how vast a role such Wizards and Witches could play on such a battlefield, especially when backed up by elite soldiers, that Shirou had labeled them as priority number one.
Them because he had sensed three magical attacks coming his way.
In that instant, as one soldier spewed green lightning arcs from his mouth and eyes, another sent some kind of psychic shockwave blasting toward him, and the Witch changed the colors of the surroundings with her magic, Shirou knew he wasn't fast enough to dodge all these attacks and still somehow survive all that firing.
He knew that the only way he stood a chance of winning was not through an indestructible defense, but a speedy offense.
He knew that to unleash that speedy offense, he must survive the initial round of firing.
For that to happen, Shirou needed to… tank the three magical attacks first.
Presently, the three magical attacks outpaced the physical projectiles as they cracked toward him.
Almost simultaneously, Shirou activated his Projection Magic.
But the actual projection didn't come into being until the three magical attacks had already landed on him.
Colors overwhelmed the space beneath the domed, white roof for a moment.
The first color was that of blinding golden rays that streamed out of Shirou, giving him a divine presence.
A long, triangular shield's transparent projection covered him, radiating nothing but holiness.
Avalon!
The second color was a green so dark that it looked black.
The monstrously thick Killing Curse landed right on Avalon, along with the Warp lightning, and… pushed Avalon right back into Shirou, making him cough up blood, Madam Villanelle's eyes popping out of her skull on the other side.
The third color was invisible but carried a bluish aura.
With blood in his mouth, eyes, and ears, Shirou's head snapped back as Compel hit him, forcing him to give up on all defenses and submit.
With his mind connected to his Inner World, he should have had the easiest time dealing with such magic. However, the magic that hit him was so strong that it rattled the Reality Marble, temporarily disrupting his Projection Magic before the swords within hacked through the invading force.
The two Psykers instantly passed out.
However, they also delayed the arrival of the fourth color.
So, before the pink came into existence, becoming a seven-layered, seven-petaled flower, a few of the Bolter rounds had already hit the target.
BOOMS rang out as the rest of the rounds landed on Rho Aias, the first two petals cracking one after another.
The Ultramarines continued to fire nonstop.
But the third petal held.
Round after round slammed into it, exploding into showers of sparks, yet the shield refused to give way, forcing the Marines to finally put a hold on their fire.
Slowly, the dust settled, all the blinding colors receding but one.
Behind the glaring layers of the seven-petaled pink flower stood the same boy, drenched in blood, and…
… carrying a smile on his face, along with the white and black swords in his hands!