Shirou revealed a smile. Although he had intruded midway into this bizarre dream, he had deduced why Angra Mainyu would manifest using Irisviel's body based on bits of information.
"I hate your smile," Angra Mainyu said in disgust. She snapped her fingers, and countless black mud around her rushed to submerge Shirou, as if responding to orders from a commander.
But the mud wasn't just submerging him - it was surging into his mind. And Angra Mainyu entered his mind along with the black mud.
Shirou found his consciousness inside his own mind. Black hands grabbed his limbs and hung him up high, like a convicted criminal about to be slaughtered.
"How should I trample your mind?" Angra Mainyu looked at him and asked with interest.
"That's for you to decide," Shirou replied seriously. "I just wonder...can we get along? Even if it's only in this dream?"
Angra Mainyu burst out laughing as if she'd heard the funniest joke. "You actually want to be friends with Evil? How ridiculous! Dream...dream... Hahaha! You think this is a dream? You fool, this is reality!"
"It's not ridiculous," Shirou said earnestly. "I'm speaking from my heart. Here, you can feel my sincerity, can't you?"
She laughed loudly again, mockingly ridiculing his naivete. But her laughter died away as she met his steady, sincere gaze.
This guy...he's serious! she realized.
A judgment beyond anything she could have imagined.
Evil was scorned. Evil was rejected... No one would affirm it, no one would accept it. Even heroes saw Evil as something foul to be cleansed away. Yet this man actually thought of getting along with Evil!
Facing Shirou's earnest gaze, she couldn't help but take a step back.
"Let me go, and let's get along, okay?" he said gently. "Angra Mainyu, All the World's Evil - those are names forced on you by others, not your true name. I want to know who you really are."
Angra Mainyu took another step back. She looked at him with the fearful, recoiling eyes of one unaccustomed to light after long confinement in darkness.
After a moment of tense silence, a frantic smile appeared on Angra Mainyu's face.
"Too late! It's too late! I have already manifested - Evil will devour everything! I will have my revenge on this wretched world, and you will feel Irisviel's wrath!"
The surrounding black mud churned violently with waves of hatred, trying to swallow Shirou.
He understood then that there was no communicating with this Evil and Angra Mainyu. The situation in this strange dream differed too much from his reality. Here, Angra Mainyu had fully manifested and been twisted by Irisviel's hatred. Like a Beast, there was no possibility of communication, only destruction. The Evil also refused to communicate, only wanting to destroy Shirou and everything else.
"That's really unfortunate," Shirou sighed. "I'm sorry, little Angra. But I'll have to destroy you now."
"Destroy me?" she cackled loudly. "I am All the World's Evil, while you're just an ordinary person! How could you possibly destroy me?"
"From the moment you entered my mind, your life has been in my hands," he sighed again.
Angra Mainyu readied another scathing retort, but paused as she noticed something wrong.
The swirling evil lingering in Shirou's mind suddenly stirred without warning, as if being sucked away by an invisible force and dragged somewhere.
It wasn't just the Evil - Angra Mainyu herself felt an irresistible pull.
The invisible vortex was sucking in all the evil lingering in Shirou's mind and soul - including Angra Mainyu herself.
"What's happening?" she panicked. "What's this force pulling me in? Is that a vortex?"
The situation exceeded even the imagination of All the World's Evil.
"This is my one special talent - an invisible vortex deep in my soul," Shirou explained. "Don't resist. I've done some experiments before - it can even absorb Crimson Moon. You won't be an exception."
"How can this be...?! How is this possible?!" Angra Mainyu paled. She whirled to face Shirou's spiritual form, demanding, "Was your plan to lure me here from the beginning?!"
"Of course," he nodded. "I calculated your every move and action ahead of time. Luring you here was the only way I could deal with you. This vortex is troublesome - it only activates when something foreign enters my mind or soul."
Disgust flashed across his face. "Still, having to personally destroy something that's been with me for so long, even if it's just in a dream...it makes me feel sick for the first time in awhile. Farewell, little Angra. If we meet again, let's have a nice chat."
"Da...Damn it!" She howled furiously, filled with hatred and resentment. She struggled helplessly as the vortex dragged her in. The evil that could destroy everything was being crushed bit by bit by the vortex.
"I see now, hahaha!" Angra Mainyu cackled as she was drawn closer to oblivion. "You're the same as me - you're evil too! You're the World's Evil! I may not be able to destroy this world or get my revenge, but you still can. You must!"
Her laughter echoed louder. "This world will fall, and you will be the one to make it happen! Hahaha!"
With that, she was ground to pieces by the vortex and disappeared completely.
Shirou paid her words no mind. To him, this was just a bizarre dream.
Angra Mainyu was crushed to death by [Mortal Awakening], freeing Shirou's consciousness from his mind. However, the black mud surrounding Einzbern Castle did not disappear with her demise.
Shirou stood inside the castle, looking at the Heroic Spirits trapped by the black mud. Without hesitation, he rushed straight into the mud.
The malicious mud immediately began destroying his body. But he pushed forward resolutely, swimming toward the trapped Heroic Spirits.
Diarmuid, Spartacus, Artoria Pendragon and Scathach...
His gaze lingered on Saber briefly before moving past her, continuing toward Scathach.
This was just a hazy, illusory dream. And in this dream, Scathach had been set as his Servant. So the method to leave this dream might lie with her as well.
With her Saint Graph intact, she was the only one still conscious. Seeing Shirou swimming toward her, while the black mud was slowly destroying him, Scathach felt extremely sad and distressed that she had dragged him into this situation.
She shouted anxiously, "Don't come here! Get out, Shirou! This isn't my main body - you don't need to save me!"
But Shirou didn't stop. Without hesitation he swam over, grabbed Scathach's hand, and pulled her ashore.
The black mud consumed his skin, leaving him looking like strips of charred meat, his body emitting wisps of white smoke. The pain was as intense as when he'd been burned by Ea before. Yet he persisted.
"Shirou..." Seeing his disfigured form, she didn't know what to say. A pained expression crossed her face.
"Don't make that face, shisho," Shirou said with a smile.
He thought it must have been quite a nice smile, but in reality it was horrifying. Yet in her eyes it seemed beautifully bright.
"I'm no coward. Also, stop spacing out. As your Master, I command you with a Command Spell - destroy the black mud, destroy...the Holy Grail!"
"I understand, Master!"
Scathach opened the Gate of Skye and destroyed the black mud. The souls of the Heroic Spirits trapped within were freed.
And so the fourth Holy Grail War in this dream came to an end.
Since Irisviel was bound to Einzbern Castle early on, the black mud only ravaged the castle and surrounding forest, without causing any other damage or casualties - except for Shirou, who was burnt all over by it.