As Olga Marie had said,
After the resolution of the first Singularity, numerous mysteries related to the incineration of human history emerged. Among them were mysteries closely linked to Rozen, causing him to feel deeply unsettled.
"Why do I resonate with the 'Ring' in the sky?"
"Why do I have a special ability to sense the presence of the Pillars of Solomon?"
"Why is it highly likely that King Solomon is the mastermind behind the incineration of human history?"
Each of these questions left Rozen's mind in turmoil.
Apart from these, there were more unanswered questions that lingered in Rozen's mind, leaving him perplexed. Perhaps, these mysteries were crucial to the existence of human history, and maybe they were important to his own existence as well.
However, Rozen had come to a realization, even amidst this confusion.
"These mysteries might remain unsolved unless we proceed to the very end."
Seeking answers couldn't solely rely on Chaldea's analysis and observations. Rozen needed to step into each remaining Singularity to gradually uncover the truth.
In other words...
"If I don't continue forward persistently, not only will the incineration of human order be complete, but these mysteries will also remain forever unsolved."
However, after experiencing the first Singularity, Rozen had realized something profound.
That was...
"My current strength isn't enough."
This was the fundamental issue.
"If my strength had been sufficient, I could have defeated Jeanne Alter during the first attack on Orleans, ensuring the acquisition of the Holy Grail and unveiling the truth of 'Dragon Witch.' That way, there wouldn't have been later cases of mistaken identity, and Jeanne Alter wouldn't have been ambushed by Lev."
"If my strength had been sufficient, even if Lev transformed into a Pillar, I could've captured him without risking my life and extracted more information."
"If my strength had been sufficient..."
Rozen's mind was filled with questions marked by " If ."
And eventually, these hypothetical scenarios coalesced into an idea.
"Repairing even the first Singularity was so challenging. What about the next six Singularities?"
By that time, he might not be able to recruit enough neutral Servants, nor could he count on local armies to fight alongside him. Worse yet, there might not be hostile Servants who would luckily aid him at the last moment.
These were problems that had to be addressed.
"I don't want to rely on luck to get through every crisis."
Even if he believed in miracles, that didn't mean Rozen could abandon his efforts.
"True miracles need to be grasped by one's own hands."
Therefore, for the reestablishment of human history, for the salvation of humanity, which seemed like a miracle nearly impossible to attain, Rozen would give his all.
"Moreover, there's more than just this world's matters."
Aside from this world's affairs, Rozen had another world's matters to attend to—the truth behind the annihilation of the Akabane clan in the Automaton World.
That also required Rozen to enhance his strength.
In conclusion, Rozen wanted to solve all these problems, and it all boiled down to one fundamental issue.
"To become stronger."
"Stronger."
"Even stronger."
There was no other way.
Given this, Rozen had only one thing left to do.
"To use the power of the 'Miracle' once more to travel to another world."
This time, Rozen would undoubtedly need to master the summoning magic for Upper-tier familiars. He also needed to thoroughly research the summoning system and Command Seal system from Chaldea, grasping the secrets of the "Crimson Wing Formation."
All for the sake of becoming stronger.
In fact, Rozen even had his eye on the recently acquired Holy Grail.
"As long as I possess the Holy Grail, my power can increase significantly."
The power of a wish-granting device, capable of fulfill desires, was undoubtedly priceless.
Even if you didn't consider the capabilities of the wish-granting mechanism, just the inexhaustible mana it contained was enough to make Rozen envious.
What was Rozen lacking the most right now?
It wasn't skills.
It wasn't knowledge.
It was mana.
"If I have an infinite amount of mana, even if I haven't mastered the summoning technique for Upper-tier familiars, I can summon countless Mid-tier familiars, enough to overwhelm enemies."
Not to mention, what the Servants that Rozen commanded lacked the most was also mana.
"With enough mana, I can elevate the combat capabilities of Servants to the limits their Saint Graph can endure."
"With enough mana, I can bestow and enhance attributes like 'Rigid Body,' 'Magic Defense,' and 'Magic Resilience' without restraint."
"With enough mana..."
Rozen contemplated these questions.
Unfortunately, this couldn't be done.
"The collected Holy Grails will be entrusted to Chaldea for management."
Olga Marie made a decisive decision regarding the fate of the Holy Grail.
The reason was simple.
"This is the source behind the appearance of Singularities. We don't know how it was created, from what origin it hails, but if we analyze the Holy Grail, we might obtain crucial information, such as the creator, the origin, the formation principles, and so on. Maybe we won't need to traverse all seven Singularities to find a direct solution when the time comes."
This wasn't just Olga Marie's perspective; it was also Da Vinci's suggestion.
"Even if we can't find another way to resolve the incineration of human history, by researching the Holy Grail, Chaldea's summoning system for Heroic Spirits could be improved. This way, we can summon new Servants, reinforce our forces. At the very least, we can utilize it as a mana source to sustain Chaldea's operations. After all, Chaldea's mana resources aren't infinite."
Da Vinci gave this suggestion with a tone quite different from her usual frivolous demeanor. Her suggestion was unexpectedly mature and composed.
Furthermore, the Holy Grail was an enemy's possession. Using it without rhyme or reason might lead to unforeseen consequences, so the decision was made to entrust the Holy Grails to Chaldea.
Rozen could only detach himself from reliance on external objects and focus on self-improvement.
With this in mind, Rozen had said that he would be disappearing within Chaldea for a period of time.
For the sake of journeying to a new world and for the sake of obtaining more time to enhance himself.
Of course, Rozen hadn't explained his reasons to anyone; he simply made this request unilaterally.
Surprisingly, this request was accepted by everyone.
Including Olga Marie.
"...I don't know what exactly you're up to, but seeing your performance in the first Singularity, I can tell you have your own reason"
Olga Marie sighed as she spoke.
There was no way around it.
Even if Rozen hadn't provided any explanations, just by witnessing the incredible abilities he used to enhance Servants' combat capabilities within the Singularities, everyone could infer that Rozen's over three-month disappearance previously wasn't merely idle time.
This time, it was probably the same, wasn't it?
So, everyone accepted Rozen's request.
"Considering that the subsequent Singularities will likely have even greater distortions and instability than Orleans, Chaldea will need to spend more time observing and deducing. Otherwise, even Spiritron Transfers could very well fail."
Olga Marie acknowledged Rozen's secretive actions.
Recalling those past events, Mash was left with one question.
"Senpai, when are you planning to go?"
Mash gazed at Rozen.
Under Mash's scrutinizing gaze, Rozen remained silent for a moment before responding.
"Tonight."