At this point, these people clearly could not spare attention for anything else. With the communicators cut off, she had no way to contact Char Siu Cat outside, and it was even less possible to waste emergency medicine on these people.
However, after seeing Shirou nearby, Chen thought of a solution.
"I am leaving it to you!"
Folding up the paper she had just written on and handing it to Shirou, Chen said.
"…Alright."
Taking the paper, Shirou did not know what else to say.
It could only be said that Officer Chen truly deserved her reputation as someone well educated. Her mind worked fast enough to come up with a communication method like sending messages by arrow.
Drawing the bow and nocking the arrow, Shirou aimed at an empty space not far in front of Swire and fired the arrow with the paper attached.
"The number of people is far lower than expected. There should still be people upstairs. Shirou, come up with me. Everyone else stays here and waits for orders."
After Shirou successfully delivered the message, Chen shifted her attention away from the infected and back to the operation.
The situation on site was not good. Leaving aside the fact that she still could not draw Chi Xiao, the destroyed communications alone had already caused her serious trouble.
On top of that, part of the team was clearly not in proper condition. Earlier, during the fight, some people failed to react in time. Although they did not suffer serious injuries, Chen felt it would be better for her and Shirou to continue upward together.
Under normal circumstances, she might have brought along a few people in better condition. Right now, although Shirou was in worse shape than usual, he was still a far better option than taking those poorly conditioned people along.
Besides, with fewer people, she and Shirou could move more easily.
Or rather… Shirou could move more easily.
After deciding on the personnel for the next stage of the operation, Chen and Shirou continued upward together.
She did not press Shirou about the gun from earlier. Right now, there were more important things demanding her attention.
There were already ambushes on the lower floors, so what about the higher ones?
The information from Char Siu Cat was limited. All they knew was that everyone was armed, and there were quite a lot of them...
Fortunately, this was the suburbs. There were barely any people nearby, so they could handle things without restraint.
Meanwhile, Shirou's expression was equally grim.
The reason was simple. Those people earlier all had orange cloth strips tied to their arms, which confirmed their identities.
Again and again, Shirou's impression of that organization had worsened.
Even though it had once been a place Archer stayed in, he still had to consider the passage of years and the terrifying nature of humanity.
The reason did not matter, because both happened to be things that could not withstand scrutiny.
Moreover, Reunion was an infected organization. Compared to ordinary people, the infected seemed even more terrifying.
He had worked as newbie at the Guard Department before, and he had also wandered through the slums late at night countless times. He had seen many things.
Thinking of this, Shirou rubbed between his brows, trying to throw these guesses and assumptions out of his mind.
"So it really is affecting me..."
Realizing his thoughts had become somewhat extreme, Shirou muttered to himself. Chen, who was scouting ahead, overheard him.
"What is affecting you?"
Although his voice had been quiet, there had been no sound other than footsteps just now. The communicators were still disabled, and she had been keeping watch on the surroundings, so naturally she heard his low muttering.
"No, it is nothing. This should be the seventh floor, right?"
Shirou shook his head and brushed the topic aside. There was no time to explain under the current circumstances.
According to his memory, the building was around ten stories tall. From the seventh floor… he could try using magecraft to scout ahead.
Scanning three more floors upward should not consume too much magical energy. If not for that strange sensation growing heavier and heavier, Shirou would not even want to spend magical energy on structural analysis magecraft.
Having not experienced mana shortage for so long, Shirou once again realized how precious magical energy was. If he had enough mana, he would have simply gone upstairs and unleashed something massive.
A burning building on top. A flaming building. Sounded pretty good.
Cough... cough... Exusiai had influenced him too much.
Squatting down, Shirou placed his hand on the floor.
Seeing Shirou's actions, Chen immediately entered another round of vigilance.
Although she had no idea what Shirou was doing, she knew one thing: do not disturb him.
After hearing Shirou quietly mutter a few words that sounded somewhat Victorian, glowing lines appeared on his right hand. Chen had already grown accustomed to strange things like this.
But watching those glowing lines spread across the floor where his hand touched—
Though "spread" was not entirely accurate, since they stopped extending after a certain distance, the orderly glowing patterns still aroused Chen's curiosity. After all, she had no idea what Shirou was actually doing.
"The eighth floor is empty, and the ninth floor is empty too. But there are some strange things there... Most of the people are gathered on the tenth floor."
After quite a while, Shirou withdrew his magic circuits and reported everything he had seen through his analysis.
"The tenth floor, huh? That matches my expectations. But what did you mean by strange things on the ninth floor?"
After hearing Shirou's explanation, Chen understood that he had just used some kind of detection-type Originium Arts. As for whether there would be problems with it… she trusted him enough on that point.
Compared to that, she cared more about the strange things Shirou mentioned on the ninth floor.
If the tenth floor was the boss stage, then having some sort of obstacle on the ninth floor was perfectly normal.
The question was what exactly it was.
"I am not sure... I can only confirm that there are some empty cans placed there."
Facing Chen's question, Shirou shook his head and said,
"It is nothing. We just need to be a bit more careful during the operation."
Chen did not mean to criticize him either. Being able to discover that something was wrong on the ninth floor under these circumstances was already impressive enough. At least they could prepare in advance.
If they had rushed in recklessly earlier, things would have ended badly.
"I think waiting for reinforcements would be better. These people are all gathered on the tenth floor. We can completely block the exits and just wear them down."
Seeing that Officer Chen's face looked even paler than before, Shirou suggested it.
What he said earlier about blasting his way upward had only been a joke. Leaving aside how much compensation demolishing a building would cost, the debris from the explosion could easily damage nearby houses as well.
Combined with the unknown trap on the ninth floor… Shirou wanted to choose a safer approach.
At the very least, he could not let Officer Chen take unnecessary risks.
"..."
After hearing Shirou's suggestion, Chen thought for a moment.
This was perhaps the safest option available right now, but they might not have the time to drag things out.
The events of the past two days had given Chen a vague but growing sense of unease.
After considering it carefully, Chen finally voiced her thoughts.
"We continue the operation. If anything seems wrong, we run immediately."
"Understood."
Shirou did not object and accepted Chen's command.
Right now, here, she was his superior and commander. All he needed to do was follow her orders.
At most, he could offer suggestions.
Still, Shirou quietly noted the positions of the windows. If necessary, he would take Chen on a round of high-altitude bungee jumping.
The version involving smashing through a skyscraper window.
And one with no return trip upward.
The two continued upward together. The eighth floor was exactly as Shirou described, completely safe and no different from the previous floors.
By the time they reached the ninth floor, both Shirou and Chen were on extremely high alert, already certain that something was wrong here.
"…Gas canisters."
Fully focused on the surroundings, Shirou immediately noticed the unusual smell in the air. Combined with the empty canisters he had detected earlier through structural analysis, he instantly understood the connection between the two.
Those empty canisters had contained some kind of gas, and the moment they opened this door, the gas would completely envelop them.
For now, he did not know what the gas actually did. After taking a small breath, he did not feel any reaction in his body.
This stuff… seemed useless against him?
Still, just to be safe, Shirou projected two gas masks.
"Thanks."
Taking the gas mask Shirou handed over, Chen immediately put it on.
It was slightly different from the ones used by the Guard Department, but since it came from Shirou, Chen did not pay much attention to it.
Or rather, she simply did not have the mental energy to care.
The discomfort spreading through her back made Chen feel somewhat dazed.
Thinking about the irregular schedule and intense workload of the past few days, she roughly guessed that her Oripathy had flared up ahead of schedule.
After putting on the gas mask, Chen took an inhibitor injection from a pouch at her waist and injected herself.
Such an obvious action naturally did not escape Shirou's notice.
If he was not mistaken… that was an inhibitor?
He was educated enough to recognize it, and Chen's condition today had clearly been abnormal. Her symptoms closely resembled an Oripathy episode; Shirou simply had not considered that possibility at first.
Only after seeing her inject the inhibitor did he finally understand.
"…Stay alert. There is no telling if there are more traps."
Shirou did not question her directly. After withdrawing his gaze, he focused on the door again.
Judging by how practiced she looked, she had likely been infected for quite some time. Since she had kept it hidden all this time, Shirou saw no need to expose it.
"Of course. This should be a gas that accelerates Originium activity. Be careful."
After injecting the inhibitor, Chen felt the discomfort in her body lessen slightly, and her mind became somewhat clearer as well.
However, the inhibitor only suppressed and slowed the pain. For now, she still had to endure the discomfort and continue the operation.
Once her thoughts cleared, Chen realized that her sudden Oripathy flare-up was definitely connected to whatever was in the air.
The only possibility she could think of was a gas that accelerated Originium activity. This substance was usually used in certain experiments. If ordinary people remained exposed to it for long periods, the Originium activity inside their bodies could increase, eventually turning them into infected.
For infected individuals, however, this stuff was a death sentence.
She did not particularly care whether Shirou noticed what she had done. Even if he had seen it, it did not matter.
After all, injecting an inhibitor after inhaling a gas that accelerated Originium activity was perfectly normal, was it not?
"Alright. Then I will take the lead. I am counting on you to cover the rear."
Shirou did not catch the deeper meaning behind Chen's words. But after learning what the gas did, there was no way he would let Chen continue walking in front.
When it came to Originium, Shirou was actually fairly confident.
After all, the people at Rhodes Island had already experimented with his blood in every possible way.
Pushing open the door, the scene inside was not as bad as Shirou had imagined.
He had expected the room to be filled with thick, colored gas, but in reality it looked almost the same as the lower floors, except for a row of empty canisters placed around the area.
"Heh, so it really was this stuff."
Through the gas mask, Chen looked at the empty canisters and confirmed her suspicions.
She had no idea where these people had gotten such things. If she had directly led a charge inside earlier, the consequences would have been disastrous.
It was not lethal, but having the Originium activity inside one's body forcibly accelerated was practically no different from being poisoned.
Just thinking about it was disgusting.
"This floor is empty. Let us head up directly."
After scanning the surroundings, Shirou did not notice anything unusual. It matched the results from his earlier analysis.
In a place filled with strange gas, neither of them had any intention of lingering longer than necessary. After leaving a warning sign near the entrance stating that the air was hazardous and locking the door behind them, the two immediately headed toward the next floor.
The closer they got to the tenth floor, the more cautious Shirou became.
Various Noble Phantasms were already prepared, ready to be drawn out at the first sign of trouble.
"..."
Following behind Shirou while staying alert for anyone approaching from the rear, Chen looked at the familiar black-and-white twin blades in his hands and could not help but think:
Were guns really that inconvenient? Would black-and-white dual pistols not be cooler than black-and-white dual swords?
It always felt like Shirou especially liked using black-and-white themed weapons. Even during sparring, he used this pair more than anything else.
The thought only lingered for a moment before Chen cast it aside. Shirou signaled to her that there were people lying in ambush behind the door ahead.
Chen also sensed an ominous feeling from beyond the door.
Exchanging glances, the two pressed themselves against the wall and moved closer.
Shirou was mainly being cautious because he could sense a strong wave of malice. He had to admit, this suddenly acquired ability was incredibly useful and had already saved him countless times.
If he only had structural analysis magecraft, at most he would know how many people were inside and the room's layout.
Now, through the concentrated malice, he could practically estimate how many people inside were holding weapons or preparing Arts to hurl at him the moment the door opened.
Leaving aside whether he would foolishly open the door directly, he had already been careful on every floor. Now that he knew enemies were waiting inside, he naturally became even more cautious.
Shirou projected several swords in front of the door, letting them float in midair before firing them directly at it.
The massive impact blasted the door open, followed immediately by a barrage of crossbow bolts and Arts flooding wildly through the doorway.
Watching the overwhelming attack, both Shirou and Chen, crouched nearby, silently felt fortunate they had not impulsively kicked the door open earlier.