This detail was not particularly important, and Illya had no intention of explaining it.
As long as someone had been paying attention to Rin's behavior earlier, they should have been able to understand what she meant.
However, it was obvious that most people's attention was focused more on Shirou. In everyone's eyes, Rin still appeared quite dependable.
Having failed to get an answer, the others could only turn their attention back to the scene before them.
Shirou and the others were weaving through the forest at high speed.
Saber's expression, however, did not look very good. She frequently glanced around at her surroundings, seemingly distracted.
"What is wrong? You seem very concerned about something nearby."
Noticing that something was off about Saber, Shirou asked.
"I keep feeling as though there is something there... Rin, has Archer spotted anything suspicious?"
Looking toward the right, Saber answered Shirou's question while directing one of her own to Rin.
Once or twice could have been dismissed as imagination, but this strange feeling had persisted continuously, and its location remained fixed.
She had been keeping an eye on it ever since she first noticed it. She had roughly estimated its position back then, and despite having traveled a considerable distance since, whatever was giving her that unsettling feeling had remained in the exact same place.
"No. Archer says visibility is poor in this forest. If you are that concerned about it, Saber, we can head over there and take a look right now."
After hearing Saber's question, Rin shook her head.
The dense forest did make visibility poor, and Saber's instincts were usually extremely accurate. Because of that, Rin had no intention of sending Archer to investigate alone.
They could have gone straight to Illya to discuss an alliance, but the suspicious location was much closer. It would be better to deal with this uncertainty first.
That way they could avoid any accidents during negotiations that might cause the alliance to fail.
After all, Illya and the others had certainly already noticed their arrival. There was even a possibility that they had mistaken the unknown presence for someone accompanying them. If that were the case, it would be the worst possible scenario.
Therefore, the best course of action was to make contact with the unknown entity first and determine exactly what it was.
If it turned out to be nothing more than Saber's imagination, then there would be no problem. But if there really was something there... and if it was something capable of making Saber feel threatened, then the situation would be far more serious.
Rin's suggestion quickly gained everyone's approval, and Archer was sent ahead to scout the area.
Strictly speaking, Shirou still had no idea what was going on, but since everyone else agreed, he had no reason to object.
Dangerous things should be dealt with as quickly as possible. That much he understood.
Thus, the three of them changed direction and cautiously advanced toward the location that Saber found suspicious.
The atmosphere became oppressive.
Neither Rin nor Saber spoke a word, causing Shirou to instinctively hold his breath as he carefully moved forward with them.
The spectators floating in midair alongside the group could clearly feel this tension as well. It spread to them, and they found themselves holding their breath too.
"A black unidentified object...? Archer, can you be a little more specific?"
Halfway there, Rin seemed to receive a report from Archer and signaled for Shirou and Saber to stop.
From the conversation, it was clear that Archer had already reached the destination ahead of them and had seen whatever was there.
Calling it the object's true appearance was not entirely accurate, however, because Archer could not properly describe what he had seen.
The best comparison he could give was that it looked like a black ghost, surrounded by countless drifting tentacles and radiating an extremely ominous aura.
Out of caution, Archer had neither attacked nor approached it. Instead, he immediately relayed the information to Rin.
"I understand. Keep watching it from there, Archer. If anything dangerous happens, retreat immediately. Do not let that... ghost notice you. Safety comes first."
After roughly understanding what the thing was, Rin decided to have Archer continue observing it until they arrived.
Or rather, until Saber arrived.
Anything capable of making Archer feel threatened was certainly not something ordinary.
"We need to move. I can sense that thing slowly advancing, and its destination seems to be the Einzbern Castle."
As soon as Rin ended her communication with Archer, Saber spoke.
At the same time, her outfit transformed into her combat attire, and the invisible sword appeared in her hand, bringing a great sense of reassurance to the other two.
The others nodded in agreement.
Saber took the lead, while Rin and Shirou followed behind her.
"Why is Shirou suddenly running so fast? I think I am going to be sick..."
The people being forcibly dragged along by the experience were carried at tremendous speed.
Even when Shirou had sprinted at full speed before, he had only been around the level of an ordinary person. Now, however, his movement speed was clearly much greater.
Combined with the forest terrain, it left some people feeling rather uncomfortable.
Frostnova, in particular, was having a difficult time. In this place, she could feel nauseous but could not actually throw up, making the sensation even worse.
"It is probably because Archer adjusted Shirou's Magic Circuits yesterday, right? Did they not say that afterward he would start moving around more like a proper mage?"
The four members of Penguin Logistics, on the other hand, looked completely unaffected.
Sora voiced her theory.
"That is right. With his Magic Circuits open and Archer around to guide him, Shirou's progress has been incredibly fast. Though compared to a normal mage, he is still a little lacking."
Illya nodded, confirming Sora's speculation.
At the same time, she snapped her fingers and slightly adjusted everyone's condition.
"Thanks... Magecraft really is amazing."
Feeling the nausea disappear from her body, Frostnova let out a small sigh of admiration.
As for whether she was marveling at Shirou's unreasonable rate of growth, or at how Illya had effortlessly solved her physical discomfort with a snap of her fingers, only she herself knew.
"The unidentified object Shirou and the others are chasing... that should be the black mud leaking from the corrupted Holy Grail, right?"
Amiya directed the question at Illya and received an affirmative nod in return.
"If Shirou at this stage comes into contact with the black mud... would that not be extremely dangerous?"
Hearing that Shirou and the others were approaching the black mud, Blaze's face was filled with concern.
Although she could not defeat the Shirou she knew, she was confident that if she were able to enter the scene and fight the Shirou in the recording, she could probably take him down within a few exchanges.
Even Shirou, before this point, could only be considered average when fighting at full capacity.
"This is the turning point of the Holy Grail War. While Shirou is unaware of it, Caster's side has already been overrun by the black mud. The illegally summoned Assassin was also used as a catalyst to summon the true Assassin, who should currently be carrying out tasks elsewhere."
Since she had been asked, Illya did not hesitate to explain the current situation.
After learning that the troublesome Caster faction had been wiped out by the black mud just the night before, everyone became even more worried about the situation.
Without comparison there was no perspective. Previously, Caster and her Master alone had caused them plenty of trouble. If the black mud could eliminate the entire Caster faction in a single night, then it was clearly an even greater threat.
Fortunately, Shirou's side currently held the initiative, giving them at least a slight advantage.
As long as Saber unleashed her Noble Phantasm, everything should work out.
Of course, that was assuming the ideal scenario came to pass.
"..."
While traveling, Shirou suddenly stopped and looked behind Rin.
Or rather, he seemed to be looking at something even farther away.
"Shirou? What is wrong?"
After running for quite some time, even Rin was beginning to feel tired. After all, she had been running while simultaneously thinking through possible strategies.
That said, this level of exertion was still trivial for her. It certainly was not enough to make Shirou stop and check on her condition.
Especially because she knew very well that Shirou's way of thinking made it impossible for him to suddenly start worrying about her at a time like this.
"It is nothing... I just felt like there was something behind us a moment ago. I am probably overthinking it."
Pulled back to reality by Rin's voice, Shirou blinked and turned around.
His gaze landed on Saber, who had stopped in the distance to wait for them, further convincing him that it had all been his imagination.
After all, Shirou did not believe he could be better than Saber in this regard. Her instincts were exceptionally sharp.
"Do not be so tense. Archer is still watching over things. If there is a problem, he will inform me immediately."
Rin did not pay it much attention, assuming Shirou was simply overly nervous after such a long run.
"Right, I know. Do you want me to carry you?"
Letting out a long breath, Shirou tried to relax before asking Rin the question.
He felt that he still had plenty of energy left, whereas Rin seemed to be in worse condition than he was.
"No! I do not! Worry about yourself first! Save your strength and be ready to run for help the moment things go wrong!"
Although she was tempted for a brief instant, Rin ultimately rejected Shirou's offer.
It was not because of her pride.
Rather, she wanted Shirou to conserve as much stamina as possible.
After all, only Shirou could persuade Illya.
"Alright. Let me know if you need anything."
After confirming that Rin did not require his help, Shirou did not press the matter further.
He simply turned around and signaled for Saber to continue moving.
The remainder of the journey went relatively smoothly, and before long the three of them met up with Archer.
"That thing has not moved at all? If that is the case, then things are looking bad..."
After learning that the black ghost had remained in the same spot the entire time, Rin frowned slightly.
Saber had just said that the thing was slowly moving, yet Archer reported that it had not moved at all during the last ten-plus minutes.
Something about that did not add up.
The worst-case scenario was that it had already discovered their movements and was remaining in place specifically to catch all of them at once.
"If we can get a little closer, I can simply use my Noble Phantasm and destroy it."
Saber did not possess eyesight as exceptional as Archer's, but based on his description she could still determine the creature's approximate location.
As for whether her Noble Phantasm would work...
If one shot was not enough, Archer could always follow up.
Compared to the possibility of failure, Saber felt that the threat posed by that thing was simply too great.
If there was a way to eliminate it, then it would be best to do so as soon as possible.
"...Then let us do that. If necessary, Shirou can support you with a Command Spell."
After hearing Saber's suggestion, Rin finally understood just how wary both Servants were of the ghost.
The fact that even Saber was willing to release her Noble Phantasm in broad daylight and before meeting Berserker later, spoke volumes about how seriously she viewed the threat.
As for Archer...
He kept insisting that he was not concerned, but his actions told a different story.
The fact that he had deliberately positioned himself between the three of them and the black ghost the entire time made his true thoughts perfectly clear.
"Command Spell support, right? Understood."
After Rin mentioned his name, Shirou nodded to show that he understood.
With everyone's roles confirmed, the four of them continued advancing.
Saber took the lead at the front, Archer guarded the rear, while the two Masters, Shirou and Rin, stayed in the middle.
Shirou was not idle either.
Throughout the journey, Rin repeatedly reminded him that if Saber's first Noble Phantasm failed to defeat the enemy, then he was to immediately use a Command Spell to allow Saber to unleash it a second time.
In the worst-case scenario, they might need to use a Command Spell to help Saber escape danger. If it came to that, she and Saber would make the decision themselves.
The reason they were not leaving that choice to Shirou was simple.
Both of them knew very well that Shirou would immediately use it to order Saber to retreat.
That was simply the kind of person he was, someone who could not bear to see others get hurt.
Under normal circumstances that was not a problem, but maintaining that mindset in the middle of a battle could become troublesome.
That was why the authority to make that decision rested with Rin and Saber.
After confirming their plan of action, Shirou seemed to sense something again and slightly turned his head toward a certain direction.
Bzzzt—
A noise like static interference suddenly echoed out.
The hairs on Shirou's body instantly stood on end.
Before he could even react, a figure stepped in front of him and Rin first.