Arknights' Lock of Heaven

Xia Yu sighed.

A knock-off is a knock-off. While it works fine, it's still...

Ugh.

If he really wanted to unleash a barrage of attacks, he could simply load the spirit origin of the Wise King Flash and fire a single King's Horn Cannon.

But the problem is the same as with the Piercing Thorn Spear: it works, but it's too wasteful of magic power.

The magic power used in a single King's Cannon shot, converted to Originium, would be enough for Terra's siege cannons to fire a dozen or so rounds.

Actually, if you really calculate it, the King's Cannon does have higher damage than the Siege Cannon, but the problem is its cost-effectiveness.

Furthermore, since the concept of using a replica weapon to carry a Noble Phantasm can reduce energy consumption, the King's Cannon can naturally do the same.

Therefore, it seems more cost-effective to build dozens or even hundreds of cannons yourself.

But that's where the problem lies.

King's Treasure and TerraTech appear to be incompatible.

But that shouldn't be the case. If Xia Yu had brought the Gate of Babylon from Type-Moon, she would have accepted it. But the key point is that the Gate of Babylon is a knock-off, given to her by Terra.

Terra gave itself something that turned out to be incompatible with Terra technology. What a hellish joke.

Seeing Kroos's lack of interest, Xia Yu guessed how much work it would take to solve this problem.

No wonder Kroos's attitude changed so drastically before and after.

Just as he was about to give up, Nian, who was studying Castle-3 nearby, spoke up.

"Actually, it's not like there's no way to solve it."

The expression on her face was very strange. After the two people on the scene turned their attention to her, she hesitated for more than ten seconds, and then she had a "what's the use" look on her face, "Or rather, I have the technology to solve this problem."

"Huh? Sister, if you could solve this, why didn't you say so sooner?" Xia Yu's face was full of regret. "I was already ready to give up, you know that?"

Nian still wore that conflicted expression, especially the way she looked at Xia Yu.

Three parts entanglement, three parts fear, three parts inquiry, and one part self-abandonment.

Heaven knows how Xia Yu could analyze her facial expressions so clearly.

"You know what demons are, right?"

Instead of responding to Xia Yu's complaints with her usual joking manner, she started talking about demons.

“I know,” Kroos nodded, then frowned and replied, “but I’ve never seen it before. After all, I’m still young. Wait, you won’t say…”

She deduced something from Nian's words and looked at Xia Yu with a look of horror.

“No, no,” Nian quickly waved his hand. “I just said that the environment inside is very similar to the land that has been contaminated by evil spirits.”

"And it's a very special kind of demon... that rejects all civilization..."

"So your machine will only be effective once it goes there."

"But this pollution is almost... how should I put it, it's like a conceptual thing. The pollution is very little, or even impossible, to harm people. It only affects things related to civilization, such as machines."

"Moreover, the effects on the machine will disappear immediately once it leaves that space."

"Then how do we even begin?" Upon hearing this, Kroos's eyes widened. It only works on machines? Isn't that a disaster?

From siege cannons to maintenance machinery, aren't they all creations of civilization?

Xia Yu sighed. Was she destined to only use the King's Cannon?

“For others, this might really be the end,” Nian said, puffing out his chest with pride. “But you have me.”

"Don't forget, I'm the designer of the Divine Light Cannon that Yan Kingdom has used for hundreds of years, and that Divine Light Cannon was designed for what purpose."

"I'm good at this!"

As he spoke, he raised an eyebrow at Xia Yu, giving her a look that said, "You've hit the jackpot."

"So, Master, you have the technology to isolate yourself from the influence of evil spirits?" Kroos's eyes lit up instantly.

What should I do? I really want it...

But to learn these skills, I'd probably have to work overtime until I die.

“We do have the technology,” Nian paused here before speaking to Xia Yu, “but you need to be mentally prepared.”

"I'm ready," Xia Yu sighed. It's good enough to have even a glimmer of hope; what more could I ask for?

“Very expensive! Extremely expensive!!!” Nian’s expression was very serious. “The so-called technology is actually just a special metal. Perhaps using this metal to build a cannon is nothing to a country, but for an individual…”

"It's expensive but there's no market for it!"

As he spoke, he pulled a metal accessory from his waist.

"The copper from Shoushan is a strategic resource of the Great Yan Dynasty. There is no precedent for its export. It can isolate the ubiquitous influence of evil spirits."

“It’s never been exported,” Kroos said, looking at the accessory in Nian’s hand with obvious envy. “No wonder I’ve never heard of it.”

Xia Yu had heard of the copper from Shoushan.

The Xuanyuan Sword was forged by the Yellow Emperor. It is made of copper from Shou Mountain and contains ancient astronomical characters. It is said that after the Emperor's death, he was buried at Qiao Mountain. Five hundred years later, the mountain collapsed and the burial chamber was empty, but the sword remained.

That's the material used to forge the Xuanyuan Sword; its prestige is off the charts.

"As long as you can get the materials, I can build it for you!"

As Nian spoke, he winked at Xia Yu, "Of course, if you don't have this channel, I still have some connections in Da Yan."

"Although we can't get too many, we can build three or four cannons. Don't even think about any more."

Although she spoke lightly, a hint of heartache still flashed in her eyes.

This is going to be a huge financial blow, but thankfully this helper is worth it, otherwise we would have lost a fortune.

Upon hearing this, Xia Yu thoughtfully stroked her chin.

Then he said to Nian, "Can I see the copper coin in your hand?"

“Here you go,” Nian said, ignoring Kroos’s burning gaze, and handed the accessory to Xia Yu. “It’s called the copper of the First Mountain, but it’s actually a special alloy. I don’t even know the exact formula.”

"You know, the Great Yan Dynasty is extremely strict about this. If even a small piece of it is found to have illegally circulated outside, it would probably take at least a thousand or eight hundred lives to quell the situation."

Nian repeatedly emphasized the preciousness of this material so that Xia Yu would know how much she had sacrificed for him.

Why worry that he won't put in the effort?

However, although her words were somewhat exaggerated, the actual situation was not much different from what she said.

For the nations of Terra, plagued by the presence of demons, metals capable of resisting demonic corruption are of utmost value.

Judging from Nian's expression, the production of this metal can be described as quite impressive.

Otherwise, the Great Yan wouldn't be so vigilant in its defenses.

High-ranking officials in other countries should also know more or less about the existence of this metal, but looking at the muscles all over the Great Yan, what do you dare to say?

If it really is a rare metal dug out of the ground, Xia Yu really wouldn't know what to do with it.

But according to what Nian said, this thing is an alloy...

Ok.

I've chosen you, Almighty Holy Grail, give me the explanation!

Then, with the wisdom of the people, they launched an operation!

Xia Yu held an accessory for the year in her right hand and a handful of soil that she had dug out from somewhere in her left hand.

With an invisible ripple, the soil in Xia Yu's left hand gradually changed shape, eventually solidifying into a silvery-white metal.

"Let me tell you, I know the Great Yan Celestial Master's Mansion inside and out. I'll give them this much face..."

As he was speaking, he saw the scene above.

Then, dumbfounded, he rushed over and snatched the silver-white metal from Xia Yu's left hand.

"What...what is this?" After a series of unique testing techniques, she suddenly turned around and grabbed Xia Yu's collar, her expression excited. "What on earth is this?"

"Why does it look so much like my Shoushan Copper?"

"Well, actually, you can think of it as Shoushan Copper in a different color," Xia Yu said casually. "So, how about it? Can this thing be used?"

"I don't understand!!!" Nian stood frozen in place after hearing Xia Yu's answer. "I can't accept this!!!"

"You just casually produced the formula for the First Mountain Copper, which the Great Yan Dynasty guarded so closely, in just two or three seconds?!"

"I can not accept!"

Nian looked on incredulously, "Who's the one in charge of forging between us? Why can't I do it?"

Back when I was forging weapons for the Great Yan, I couldn't help but be envious of this thing.

However, while Da Yan strictly controlled the formula, it was extremely casual about the finished metal products.

Hey, if you're so capable, then analyze it. If you can analyze it, that's your skill.

With this attitude, how can we tolerate them?

Then they began analyzing the copper from Shoushan.

But who would have thought that three years later, then another three years, and many more three years passed. The weapon that he had promised to forge for the Great Yan was finished, but he, who was in charge of forging, still couldn't figure out how it was made.