[Answer]
Are you certain, Host?
"What do you mean?" Zeke asked in confusion. He was completely unaccustomed to Akasha questioning his decisions.
[Answer]
In the past, Host has expressed notable reluctance to progress along this path.
Zeke grimaced, acknowledging the point. The option to use Soul Magic was initially intended as a contingency, reserved for use only if all else failed. However, mere hours later, he found himself ready to embark on this path. He fell into a brief silence, carefully reevaluating his decision once more.
Taking a deep breath, he leaned back against the perfectly smooth stone wall of his hideout and closed his eyes. When he opened them again, he was in the world of his Mind's Library — Akasha's home.
In front of him, surrounded by an endless expanse of white, sat a young woman with white hair, blue eyes, and a curvaceous body. Akasha's chosen form was an amalgamation of the most beautiful women Zeke had ever met. For a moment, the sight stole his breath away.
However, he managed to get his bearings an instant later, reminding himself of his purpose here. "I am certain, Akasha. Tell me."
"Host needs to establish what he wants to achieve by doing this," Akasha said, her monotone voice just the same as usual.
Zeke fell into deep thought. Given the fact that he was not entirely certain what could be achieved through Soul Magic, he didn't yet have a concrete goal in mind. Nevertheless, it was essential that he did as much damage to the Archmage as possible if he wanted to give his side a chance. "What's the most damage we can do without being detected prematurely?"
Akasha closed her eyes while silently mumbling, "Calculating — 10%… 15%… 35%… 62%… 84%… 97%… Calculation complete — optimal plan of attack determined."
Zeke leaned forward in excitement, curious to find out what Akasha had come up with.
A moment later, she opened her clear blue eyes and stared intently at him. "A strategic approach with optimal success probability has been established. However, numerous foundational assumptions rely on speculation without practical evidence. Does Host wish to proceed?"
"It doesn't matter," Zeke said. "I didn't expect anything else, given the meager amount of practical experience we have. Just tell me what you got."
"Affirmative," Akasha said. "The optimal approach was determined to be the deliberate creation of a Soul-Body mismatch."
Zeke's brows shot up. A Soul-Body mismatch? He had never heard of that term, and he was pretty sure Akasha had made it up just now. "Can you explain?"
Akasha nodded. "Host has previously ascertained that the Soul is comprised of a compilation of experiences, documenting every moment of an individual's life. Is that correct?"
"That's right," Zeke said. "When I… accidentally consumed the Soul of the spy, his memories streamed into me. Meanwhile, his essence was getting lesser in equal measures."
Despite his hesitation and obvious unease with this subject, Akasha's manner of speaking remained completely serene. "I believe that Host has made an accurate judgment regarding that experience. However, a crucial element is missing."
"Enlighten me," Zeke demanded curtly. He wasn't too pleased with the direction the discussion had taken, as this memory remained one of his most dreaded experiences.
"Affirmative," Akasha replied, wholly unfazed by his emotional state. "The crucial element Host has overlooked is the man's death."
Zeke furrowed his brows. His unease slowly turned into curiosity as he recalled the event. Thanks to his [Perfect Sensory Recall], his accounts of the events had not been distorted or lost.
A moment later, the scene of a prison cell was projected in the air between Zeke and Akasha. It was a miniature recreation of one of his memories. In the scene, two people were sitting across from each other, completely motionless. One of them was a young man with blood-red hair, and the other a hideously deformed figure who had been strapped to a metal chair. It was the moment right before Zeke had drained the man's Soul.
However, he was only able to observe the happenings of the mortal plain, not the interplay between Souls. Still, this was the first time he actually saw how the man had died, as he had previously only been confronted with the aftermath.
With morbid curiosity, Zeke watched the scene of the two people confronting each other. It didn't take long for the prisoner to show a reaction. First, his face started to twitch. Then, his entire body started to spasm. Only a few moments later, he started to scream uncontrollably. This must have been the moment the guards called for David.
However, what happened next was utterly unexpected: silence returned to the room.
The prisoner went from violently shaking and screaming to utterly still in an instant. It was clear that he had died. Yet, there was no sign of Zeke waking. Instead, the young man in the recording remained seated peacefully, his eyes still closed. It wasn't until several minutes later, when David came to shake him awake, that he was awoken from his trance.
Zeke looked up from the recording, the question clear in his eyes. "That's strange," he said. "I remember that I was still draining his Soul when David woke me."
Akasha nodded with a blank expression. "I suspect that to be true. Nevertheless, it should be noted that the individual had perished long before that point."
"Interesting." If that was true, then that meant that he had somehow locked the man's Soul in place, even after his death. And that wasn't the only implication of note. He glanced at Akasha. "What was it that actually killed him?"
Akasha smiled, causing Zeke to be dazed once more. It was the first time he had seen her express any kind of emotion. In spite of what he had thought, the gesture looked completely natural on the face of the usually emotionless girl.
"A Soul-Body mismatch," Akasha explained proudly.
"Excuse me?"
"A Soul-Body mismatch," Akasha repeated. "That is what caused his demise."
"I am not familiar with that term," Zeke said, slowly getting back to his senses.
Akasha nodded. "It is a word I created to describe this phenomenon. Does Host like it?"
Zeke cocked his head, regarding Akasha with interest. There was a peculiar glint in her eyes, like a baby bird begging its mother for food. "How about you describe the phenomenon to me first?"
"Affirmative," Akasha said, returning to her placid expression. "This phenomenon occurs when the body rejects a Soul because it no longer recognizes it as part of the system. It is similar to the body fighting against an infection."
Zeke looked at her in surprise. "That's what killed him? His own body?"
"It is the sole explanation that aligns with the facts," declared the spirit.
Akasha was right. There shouldn't be a problem with a Soul losing parts otherwise. It was no different from returning to the past, to the state before making those memories. He could also determine that the removal of memories wasn't inherently damaging, as he had experimented with that concept quite a bit. He had even split off a small part of his Soul to infiltrate the Archmage earlier today.
"Tell me more about this… Soul-Body-Mismatch," he demanded.
Akasha looked pleased upon hearing Zeke adopt the term she had invented. "The phenomenon occurs in varying degrees of intensity," she explained. "However, even after the slightest bit of the Soul goes missing, the body reacts negatively."
Zeke raised a brow, clearly about to object. Yet, before he could get a single word out, Akasha continued. "Yes, it happens every time Host sends out a Soul probe as well. However, in those cases, the body adapts quickly. The mismatch will only manifest in a momentary feeling of unease."
Zeke closed his mouth.
"The more frequently this happens, the more severe the reactions will be. In instances where segments of the Soul persistently vanish over an extended duration, it is speculated that the body will begin to manifest signs of illness, such as headaches, migraines, lethargy—"
"Wait a moment," Zeke interjected. "If a disconnect between body and Soul is such a serious issue, then why did the Dragon try to steal my body? Wouldn't he have killed himself by doing so?"
Instead of Akasha, a deep, rumbling voice from somewhere in the void answered his inquiry. "Kill me? With that pitiful body of yours? I don't think so."
"Why not?" Zeke asked.
"If a Soul is vastly more powerful than its vessel, it can easily overpower the body's resistance," Akasha explained instead of the Dragon. "Furthermore, Host was still an Apprentice Mage at that point in time. This is relevant because the connection increases with each advancement, with body and Soul becoming intrinsically linked at the Archmage level."
"Doesn't that mean that it is going to be vastly more difficult to damage the Soul of an Archmage? Can we even kill him?"
"It is highly improbable that we will successfully terminate his life using this method," Akasha stated. "He is likely to resist well before we reach that juncture."
"Then what is the point of all this?" Zeke asked. "Wouldn't it be better to do as much damage as quickly as possible instead?"
"Negative," Akasha stated. "It has been concluded that we can inflict more harm by gradually eroding his Soul over time."
"And then what?" Zeke asked with a rising sense of dread.
"Host will have to terminate him in the real world," Akasha said nonchalantly.
"Are you insane?" Zeke burst out.
Akasha tilted her head. "Negative. My cognitive processes are rational, with no abnormalities detected."
Zeke rolled his eyes. "Then tell me how I can do that. Even a weakened Archmage can kill me with a slap."
"That is incorrect," Akasha stated with confidence. "However, it is true that Host is unlikely to emerge victorious in a confrontation, even against a weakened Archmage."
"So?"
"…Host will have to think of something to bridge this gap," Akasha said.
Zeke stared at her for a long moment, a mixture of disbelief and exasperation warring on his face. What kind of a plan was this?
Yet, the longer he thought about it, the calmer he got. Akasha was right. This wasn't her problem to solve; it was his. She had already pointed the way, giving him the best odds possible. If he couldn't overcome this final hurdle on his own, he had no business being here.
He took a deep breath, centering his mind. "You are right, Akasha. Just tell me how to start, and I'll… think of something." Zeke promised, a queasy sensation settling in the pit of his stomach. He could only hope that he would actually be able to live up to those expectations.
After all, his life might depend on it.