The Grand Priest Ymir's knowledge of Glintstone magic was extraordinarily vast.
Or rather, as Rellana's magic instructor, in terms of pure magical ability, he was even stronger than the Twin Moons Rellana. Rellana's Twin Moon's magic had been modified with Ymir's help, making it an improved version of the Full Moon Queen Rennala's Full Moon magic.
What surprised Aoko the most was that Ymir, a Glintstone sorcerer from Caria, actually knew how to use the Night Shard magic originating from the sorcerers of Sellia!
"Nothing is surprising about that," Ymir said calmly. "The origin of Carian Glintstone sorcerers traces back to the ancient star-gazers—descendants of the Nox. The sorcerers of Sellia merely inherited a portion of that knowledge by chance."
Aoko and Touko temporarily stayed in a room within the church, becoming temporary magic students under Priest Ymir. They studied nearly all the Glintstone sorceries that had ever appeared in the Lands Between, including many spells personally created by Ymir.
As a trade-off, the Aozaki sisters agreed to accompany the Swordhands of Night, Jolan and Anna, in clearing out various enemies near the Cathedral of Manus Metyr. These enemies included all sorts of monsters as well as wandering horned warriors.
Although the Swordhands of Night sisters remained cold toward Aoko and Touko, their attitude had shifted from initial hostility and vigilance to mere indifference and tolerance—a significant improvement.
To Aoko and Touko, Jolan and Anna's devotion to Ymir was understandable. As children raised by Ymir since childhood, their admiration and reliance on him were natural. Besides, in a dangerous place like the Lands Between, being wary of strangers was only logical.
"This spell is a lost forbidden technique from the Eternal City," Ymir remarked as he held an ancient scroll, explaining magic to Aoko and Touko. "It summons a forbidden darkness capable of absorbing all starlight conjured by magic, making it the ultimate defensive spell."
"But that was not its original purpose," Ymir continued. "The Primeval Current was, in essence, a gateway to the Greater Will. Though the version recreated through Glintstone sorcery is but a pale imitation, it was still the cause of the Eternal City's downfall. Someone exploited this spell's origins, bringing forth calamity."
"Then is there a risk in using this spell?" Aoko asked. "If the original version was responsible for the destruction of the Eternal City, does that mean we might also encounter disaster?"
"Ah, that won't be an issue," Ymir said after some thought. "However, you must be careful. The Primeval Current indiscriminately absorbs magic, meaning it can nullify friendly spells as well. That is the real danger you should be wary of."
Aoko nodded and carefully noted down the key points of the spell. She wasn't using her usual spellbook but a newly dedicated notebook specifically for recording Glintstone sorcery.
"As a Glintstone sorcerer, I have always sought to understand the stars and the life within them," Ymir continued. "Long ago, somewhere in the dark expanse of the cosmos, an explosion occurred. And from that explosion, stardust was born—stardust that ultimately formed us."
Aoko and Touko exchanged glances. Does the Lands Between have a theory akin to the Big Bang?
"In other words, we are all children of the Greater Will," Ymir said with a smile. "Isn't that poetic? Isn't it beautiful?"
"Are you saying that life in the Lands Between originates from the falling Glintstone?" Aoko asked. "That the life inside Glintstone is the progenitor of all species in this world?"
"Exactly. You two truly have a natural talent," Ymir said with admiration. He believed that the Aozaki sisters' potential as Glintstone sorcerers rivaled even that of the Full Moon Queen and the Twin Moons sisters. "It's a pity that so few people know this truth. Or perhaps, they simply choose to ignore it, chasing after more superficial pursuits instead."
When Ymir first read Rellana's letter of introduction, he agreed to train the Aozaki sisters but held no particular expectations for them. To him, they were no different from the students he had once taught at the Carian Study Hall—seeking to study Glintstone sorcery merely as a means to gain power.
However, after some time teaching and conversing with them, Ymir keenly noticed that the Aozaki sisters possessed a unique magical system distinct from Glintstone sorcery—knowledge originating from beyond the Lands Between.
This did not surprise him. After all, the very roots of Glintstone sorcery also came from beyond this world. He had no intention of demanding that the Aozaki sisters divulge their knowledge. He had yet to perfect his research—why would he covet another system's secrets?
"Speaking of which, you two have the potential to become true gods," Ymir remarked, setting down the scroll and gazing at the Aozaki sisters with a serious expression. "Do you know the difference between a demigod and a god?"
Touko had no idea and simply shook her head. Aoko thought carefully but found no clear answer in her memory—only vague speculations—so she also shook her head.
"A demigod, no matter how powerful, can never ascend further to become a true deity," Ymir explained. "The key difference lies in whether one possesses their own Law."
"And what is a Law?" Ymir continued. "It is the principle that governs the world—a unique order of existence."
"Before a god ascends, their Law has limited influence," Ymir said. "Though still formidable, it remains rejected by the world itself. If the god-to-be loses their divine power, their Law will gradually fade into nothingness."
"However, once a deity fully ascends, everything changes. Their Law becomes a foundational truth of the world, fully accepted into reality itself."
Aoko was beginning to understand what Ymir was trying to convey.
"You two, though not demigods, each bear unique Laws from distant lands," Ymir said. "At first, I suspected that Miss Touko might be an inheritor of the Golden Order, but after careful examination, I realized that was not the case. Yours is a Law that grants souls eternity—dangerous yet alluring."
"And Miss Aoko, your Law revealed to me a completely unfamiliar cosmos," Ymir sighed. "When I first saw your Law, I felt an instinctive fear, because within it, I glimpsed true finality."
"But after deeper reflection, I realized this may not be a bad thing," Ymir said with a smile. "All things that begin must come to an end. The near-collapse of the unchanging and immortal Golden Order is the best proof of this truth."
"The more this world tries to preserve its pristine form, the more rotten its foundations become."
"The very roots of this world have long since fractured and twisted. No matter how much people struggle, it is all in vain—that is the tragedy of the Golden Age."
Professor Ymir, are you sure it's okay to say such blasphemous things so casually?
Or perhaps this was precisely why he left Rellana's side—because his theories were too radical, and he feared bringing unnecessary trouble to his student?
Aoko and Touko pondered this silently.
"You have learned most of what I can teach," Ymir said with satisfaction. "The next step involves my original research, but before I continue teaching you, I need you to complete a task. Consider it your final exam."
With that, he handed Aoko a strange flute. It looked like a finger with numerous small holes drilled into it.
Along with it, he gave them a map pointing to a peculiar location.
"If anyone can bring true renewal to this world, it might just be you," Ymir murmured as he sat on his ornate high-backed chair. "Go, sound the bell in the ancient ruins. You, travelers from afar, are bound by the radiant stars, and in turn, the stars shall shine because of you."