If Shinji knew Kiritsugu's thoughts, he would laugh himself awake from dreaming.
His request for Scathach to intervene and save Justeaze was not meant to disrupt Kiritsugu's plans. It was simply an attempt to gain something from Justeaze. He never expected Kiritsugu to dig his own grave.
Scathach's action plan for tonight was as follows: drive from the city to the foot of the Einzbern forest, then hike up the mountain. Just as she found Caster's location, she received a message from Shinji, instructing her to confirm the condition of Justeaze.
When Scathach arrived at the back of the mountain, Justeaze was already engaged in battle with Kirei and holding her own.
Upon receiving this news, Shinji finally let go of the heavy stone that had been weighing on his heart. He was worried that Justeaze would encounter other Servants. Justeaze lacked a specific class template, and she had no combat experience in her lifetime. Even if she had developed new combat magecraft, she couldn't possibly match up against a Servant. (This was limited to the current Holy Grail War. Against non-combat Servants like Andersen or Shakespeare, Justeaze would have a chance of winning.)
But if her opponent was Kirei, Shinji had no worries.
Although Kirei was powerful in combat and had extensive battle experience, he was still bound by the limits of a human. His fighting style, focused on Black Keys and Bajiquan, did not exceed the scope of "interconnectedness" and "myriad changes" that Justeaze could handle. Even if Justeaze couldn't defeat him, it wouldn't be difficult for her to retreat. Scathach also agreed with this assessment.
Having confirmed this, Shinji made a quick decision and changed his objective once again, instructing Scathach to head to the castle. This led to the subsequent scene of saving Kenneth in front of Kiritsugu, extending a favor to Lancer, and incidentally improving Saber's opinion of him.
Irisviel didn't have as many thoughts as Kiritsugu and Shinji. Her view on the matter was simple: "Shouldn't we contact our family? Perhaps Lord Acht (Acht Einzbern) knows something."
Upon hearing his wife's suggestion, Kiritsugu appeared hesitant.
The suggestion itself was not a problem. Kiritsugu and Irisviel couldn't possibly have as much knowledge about the Einzbern family as Acht, the humanoid terminal capable of central system production. Asking Acht for information would provide a clue, regardless of the response received.
The conservative isolation of the Einzbern family made it extremely difficult to contact them. The Einzbern family lacked modern communication devices, and the alchemical communication devices were only possessed by Acht and could only be used at fixed times and through specific nodes, which did not include the Einzbern forest in the Far East.
To contact the Einzbern family, Kiritsugu had to go through three intermediaries. First, he would contact his intelligence personnel, then transfer to one of the few peripheral bases of the Einzbern family, and from there, go to a specific node. These nodes also did not have modern communication devices and strictly adhered to the traditions of the Einzbern family, relying on the alchemical devices of the nodes to contact the head of the family, Acht.
Just the process of contacting Acht alone would take three to six days. If the time for Acht to search for information and provide a reply was taken into account, it would probably take ten days to half a month. By that time, the Holy Grail War might already be over, and the answer would be of no use.
Apart from the difficulty of communication, Kiritsugu also had some concerns about the mysterious woman's reaction. Although she was related to the Einzbern family, her actions and behavior indicated that she was not on the same side as the Einzbern and even had conflicts with them. If Kiritsugu rashly contacted the family, it could potentially anger the woman. If she was pushed into opposition, it would be disastrous. Regardless of whether she had any connection with Assassin, she displayed combat abilities made Kiritsugu cautious.
In the end, Kiritsugu shook his head and said, "Forget it."
"Okay, I'll follow your lead." Once her husband had made a decision, Irisviel would comply without questioning—such was the understanding between them as a couple.
"Saber, I'll leave the security of the castle to you. I'm going to chase after Kenneth."
Having said that, Kiritsugu didn't wait for Saber's response. He left the dining hall, walked past the devastated castle gate, and disappeared into the night. Even if Assassin managed to rescue Kenneth, Kiritsugu had no intention of giving up. He would stop at nothing to achieve his goal.
Saber wanted to say something, but looking at Kiritsugu's resolute figure, all she could do was swallow the words that had reached her lips and lower her head in frustration.
Irisviel noticed Saber's demeanor and turned to ask the young knight who she was close to, "Why didn't you say anything? Are you thinking of taking down Caster?"
"Because I need to protect your safety and Miss Maiya's safety."
Saber lowered her head and looked at her left hand, which was wearing a silver ring used to secure her unconscious thumb. If her left hand was unharmed, Caster would already be dead.
"It's no longer safe here. Miss Maiya can't move, and you need to take care of her. If enemies invade while I'm gone, you'll be in danger, especially that man who injured Miss Maiya..."
"Kirei Kotomine," Irisviel instinctively uttered the name that made Kiritsugu fearful.
"I've examined Miss Maiya's body. More than half of her ribs are broken, and her internal organs have varying degrees of damage. Just two strikes caused such injuries. This man is powerful." Saber gave a high evaluation of Kotomine's Bajiquan.
"Powerful? Is that what even you, Saber, say?" Irisviel's hands involuntarily clenched, showing her nervousness.
"Yes, he is very powerful." One of the principles of a knight is justice, and Saber wouldn't belittle the enemy just because they are adversaries. "Based on the knowledge bestowed upon me by the Holy Grail, there are not many humans stronger than him. However, Irisviel, rest assured, I'm talking about humans, not Servants. Even with just my left hand, I can easily defeat him."
The last sentence instantly turned Irisviel's worries into joy. "Really?"
"I swear on my knight's honor." Saber lightly tapped her left chest with her right fist. No matter what, she would protect the woman in front of her.
"I believe you, Saber." Irisviel walked up to Saber and held her hands. "I entrust Miss Maiya and myself to your protection."
"Yes, I promise." Saber's serious expression and upright posture were worthy of her title as the King of Knights. However... this exemplary knightly stance was disrupted by an unmistakable rumbling sound.
Saber's face suddenly turned bright red, and she stammered, "Um... well... I'm sorry, Irisviel. I don't feel particularly hungry, but it seems like my body needs nourishment."
"Okay, okay, I understand." The corners of Irisviel's mouth involuntarily curled upward. "It's inevitable to feel hungry after battling Caster. Please wait here for a moment, I'll prepare something for you to eat."
"Thank you so much, Irisviel!"
Upon hearing that there was food, Saber's eyes lit up, and a mix of heroic, shy, and excited expressions made her look especially adorable.
Seeing Saber like this, Irisviel's mood improved even more.
"What should we have today? Salamander soup? How about adding some wasabi that Japanese people love?"
That's right, Irisviel excelled in the legendary dark art of cooking!
PS: Kiritsugu's combat power, comparable to a Servant, must be enhanced by Command Seals. In "Fate/Zero," Kirei personally gave an evaluation that both sides were cheating in their final battle, which elevated them to the level of Servants.