In the Scandinavian Lostbelt, the ice and snow castle where Scáthach-Skadi resides can be considered a landmark. A structure entirely made of ice would seem incredibly unique even in modern Earth.
The opulent upper levels belong to the palace; the dungeons lie below. Entering the dungeons from the stairs, everything in sight is crafted from ice and snow.
Illyasviel spoke: "In this Lostbelt, is there only ice and snow?"
"That's right, dear Illya. It can't be helped; the environment is just that harsh. Her Majesty's power is mostly used to sustain human life, leaving the castle interior without much in the way of heating measures," Li Mo explained.
The Servant from Proper Human History, Illyasviel, accepted the reality of her capture. Leaving aside that she was no match for the powerful Snow Mountain Goddess, just this enigmatic mage and his so-called "Fairy Transformation Spell" was a complete special attack against deities.
—Unpleasant memories surfaced. Berserker was immensely powerful. The reason he lost to Archer was because he possessed Divinity, and that golden-haired Archer had a Noble Phantasm like Enkidu, which specialized against gods.
Illyasviel touched the area over her heart but paid no attention to the mage.
Soon, however, she felt a sensation of warmth.
Looking up, she saw they had reached the end of the dungeon. Here was a door leading deeper underground, and the warm aura emanated from within.
The fusion of three goddesses within Illyasviel granted her extensive magical knowledge. So much so that she could tell at a glance that the space beyond that door was filled with various heating magical arrays.
Recalling what the mage beside her had said, she asked: "Is this your doing?"
"Of course. My workshop should naturally provide the best environment for myself. To facilitate smooth thinking, right?" Li Mo pointed to his head.
Even as a superhuman, he would hardly die from environmental factors. But the speed of his brain's operation could still be affected by the environment.
In a cold environment, his mind would focus on resisting the cold. This would interfere with normal thought processes. It was like a computer throttling performance to reduce heat.
"This is the dungeon, right?"
"Yes, does Illya have something to say?"
"Why... why would you build your workshop inside the dungeon?!" Illyasviel exclaimed in surprise.
Li Mo put on an innocent expression. "Because the workshop was remodeled from the deepest dungeon cell."
"No, I mean..." Illyasviel paused. "Why would you even think of building your own workshop inside a dungeon!"
"Because it's quiet enough. Alright, let's not chat here. Let's go in first. Later, would you like coffee or tea? Though, there are no sweets. I used them all when aiding my village."
Li Mo strode ahead into the workshop. Illyasviel looked at his back and hesitated for a moment.
In reality, the restraints placed by Scáthach-Skadi had already vanished. Illyasviel was free to move as she pleased, even to leave this castle.
Because even her supposed overseer, Li Mo, who claimed to know Illya, wasn't paying attention to her.
"Why aren't you coming in, Illya?"
"Aren't you worried I'll escape?" Almost by accident, Illyasviel asked.
"Escape? Illya, didn't we just discuss this?" Li Mo said. "But it's fine, I can explain again. Even if you successfully escape, it doesn't matter. Her Majesty's reach extends across the entire land, Illya. Even if you flee from here, you'll be captured again. The difference between a Divine Spirit-level Servant and an ordinary Servant is too great."
Only a Divine Spirit could make Her Majesty glance their way slightly.
After weighing the pros and cons, Illyasviel followed Li Mo into the workshop.
The interior of the workshop was many times warmer than outside. Upon entering, she could see a massive container at the center, holding flames within.
Those were no ordinary flames; Illyasviel could sense the destructive aura they contained.
"Still leaking, huh? That's troublesome. No wonder it felt excessively hot when I first came in."
Then, the young girl saw the mage activate some kind of Mystic Code, and a reddish liquid flowed into the area around the container. The radiance of the flames was instantly obscured.
Illyasviel asked: "What is that?"
"If you're asking about the flames, that's the apocalyptic fire from Surtr. If you're asking about the red liquid, that's a personal secret," Li Mo said. "As a mage, one's research cannot be easily disclosed to others."
Illyasviel said, "You explained the principle of the 'Fairy Transformation Spell' to me."
"That wasn't crucial research. Besides, the principle is simple. What's difficult are the harsh conditions for implementation. Can ordinary people borrow the power of Christianity? And even if they could, how would the Holy Church react?"
"So you're not worried about the Church?"
"Do you think there's any Church in this Scandinavian Lostbelt?" Li Mo said. "The conditions here have persisted for three thousand years. The divergence from Proper Human History also occurred three thousand years ago. That's a thousand years before the birth of Jesus, before the Star of Bethlehem shone."
Illyasviel understood his meaning.
If Jesus hadn't even been born, how could there be a Church?
"Illya, would you like tea or coffee?"
"Don't you have any soft drinks?"
Li Mo was taken aback, slowly retrieving a beverage from his inventory. "My stock isn't plentiful either."
Most of the food had been allocated to aid the village. But drinks weren't necessary. Over half a year, he had consumed most of his personal reserves. The small portion remaining was intentionally saved. As a hoarder, he could use items, but he would never let any item's quantity reach zero.
That's how the drinks were frugally preserved.
"Don't make such a reluctant face. It's like I did something wrong. Am I going to live in your workshop from now on?"
"Strictly speaking, next to it. I haven't used up all the space on this dungeon level. There are still cells further inside. I'll clean one up for you later," Li Mo said. "Her Majesty didn't specify your range of movement either. So just try not to leave my workshop, alright? That request isn't too much, is it?"
"I suppose... it's acceptable?"
Illyasviel agreed to the condition. Then, she pressed further: "You mean, I can enter your workshop?"
"Come in if you want. I personally don't mind."
"Aren't you worried?"
"Worried about what? The most dangerous research project, I was already close to abandoning. Giving up now is still fine. As for other projects..." Li Mo smiled without elaborating.
Illyasviel did not continue the conversation with Li Mo.
For a period of time to come, she would be under house arrest, confined here. As for how long that would last?
That, no one could know.