Lily quickly finished her assessment of Aaron:
Poor; of no help to her basic studies; someone she could consult on more advanced magical questions; unafraid of trouble, so she could use his name when encountering difficulties; a bit of a trickster by nature, but as long as she threw him out there, he’d end up tricking outsiders.
Lily could only comfort herself: It wasn’t that bad.
She’d chosen her own mentor—what else could she do? She could only follow him all the way down this path.
Aaron narrowed his eyes at her. “You seem to be thinking something rather impolite.”
Lily refused to admit it. “Teacher, what are you talking about?”
“…Never mind.” Aaron felt it was a bit foolish to argue such matters with Lily. Was there anything a magic wand couldn’t solve? Miss Emma was indeed ahead of her time—worth learning from!
Aaron stopped joking with Lily and turned to another serious matter. “How’s your collation of the theoretical part of the Light Breeze Technique expansion method coming along?”
Back when Lily had defeated Chris in the arena, many people had already been curious about that move of hers.
But it was Lily’s trump card, so it wasn’t convenient for anyone to press for details about the spell. After all, it might affect the ongoing practical assessment.
Even if someone asked directly, Lily wouldn’t have said anything.
Now that the assessment was over, there was no need to keep it under wraps.
Lily handed Aaron a few sheets of manuscript paper, looking a bit troubled. “Teacher, this is what I’ve compiled, but I’m not sure I’ve explained things clearly or whether others will understand… Could you take a look and give me your thoughts?”
For Lily, it was common sense that “air is composed of multiple gases” and that “gases can be toxic.”
But people in this world had no such concepts.
If Lily simply said, “This Light Breeze Technique of mine actually separates different gases, then uses one of them to envelop the target and suffocate them,”
the vast majority of people would think she was talking nonsense:
Isn’t air just gas? What makes you think air is made up of different gases?
Why would being enveloped by one type of gas cause poisoning? Why don’t we get poisoned from breathing normally?
…
Well, since Lily had actually performed the spell, it couldn’t be entirely dismissed as nonsense, but it was true that everyone found it perplexing.
To make people understand, Lily would have to thoroughly dissect these common-sense notions.
And that was where the biggest problem arose: common sense, as deeply ingrained concepts, is very convenient to use directly. But when you try to explain their ins and outs clearly, it’s not something you can cover in just a sentence or two.
Aaron didn’t respond directly. He first flipped through Lily’s manuscript.
“Expanded Light Breeze Technique: Gas Layering Method” — Lily had imitated the style of this world’s magical theoretical discourse, with a structure somewhat similar to modern papers.
The introduction was like an abstract, briefly outlining the core of the expansion method and its effects.
In the main body, Lily focused on explaining two major concepts.
First, air is composed of many different gases, such as oxygen and carbon dioxide.
If Lily remembered correctly, she had previously learned about the experiment using red phosphorus combustion to determine the specific oxygen content. In that experiment, red phosphorus was key—it burned by consuming oxygen and formed a solid, which caused a decrease in air pressure, providing a measurable “variable.”
But she didn’t even know if she could find red phosphorus in this world. If other substances burned and re-formed gases, that would only create experimental errors.
Not a big problem, though. Lily didn’t plan to make things that complicated. She was studying magic, not doing actual scientific research.
She didn’t need to explain the exact percentage of oxygen—just demonstrate its existence.
Lily used the simplest method: the candle combustion experiment.
By inverting a transparent cover over a burning candle, the flame would gradually go out, indicating that the gas supporting combustion inside had been consumed. She called this combustion-supporting gas “oxygen.”
So, did that mean no gas existed inside the cover anymore?
At the very least, limewater could prove the presence of carbon dioxide…
Well, that method wasn’t ideal. Limestone and limewater weren’t rare in this world either, but then Lily would have to explain why cloudy limewater meant carbon dioxide was responsible.
She cut that part and replaced it with a more magical explanation: “Just sense whether air-element exists within the covered area.”
The second part explained that oxygen was necessary for breathing. Without oxygen—only other gases—suffocation would occur.
Actually, this wasn’t entirely accurate either. Breathing pure oxygen could also cause poisoning. But this wasn’t the time to nitpick details; the key was to get the general framework across.
Lily used the first experiment as a basis: placing a mouse into that transparent cover after combustion. When the mouse showed signs of suffocation, it demonstrated that the consumed gas—the one that supported combustion—was also the one required for breathing.
In summary, the essence of her expansion method was to layer the gases in the air, separate out the oxygen, and specifically manipulate carbon dioxide to cause suffocation.
Lily also left a hook at the end: Did the other gas components in the air have similar effects? She believed the answer was yes, and welcomed anyone to conduct similar research.
“Oxygen? Carbon dioxide? Your naming is a bit strange, but also rather interesting…”
Aaron murmured thoughtfully, and a spell formed in his hand—precisely the carbon dioxide version of the Light Breeze Technique that Lily had described.
Aaron had a feeling that Lily wasn’t just randomly naming these gases, but was pointing directly at their very essence!
Then again, was it really Lily who had named these gases?
Heh. The mysteries of time were no less profound than dark magic. She had survived temporal magic and “seen” certain things, “perceived” certain essences—that was perfectly normal.
Aaron didn’t intend to dig deeper.
He simply raised his hand, and a magic rat confined in the lab was teleported over, landing squarely within the range of Aaron’s carbon dioxide technique.
The magic rat squeaked and frantically tried to escape, but the Light Breeze Technique followed it like a shadow. Before long, the squeaking grew faint, and the rat collapsed silently to the ground.
Lily stared at Aaron in utter shock.
Not so much at the power of his magic—after all, the same spell cast at his rank would naturally be on a completely different level from hers.
Lily had to worry about her wind being blown off course, or the target escaping on its own, but none of that was an issue for Aaron.
What shocked her was that Aaron had truly mastered this modified Light Breeze Technique in a single go!
Again: If you can’t understand it, if you can’t conceive of it, you can’t cast the corresponding spell.
This was an eternal, unbreakable rule, unaffected by your rank or the spell’s rank.
Even a legendary mage needed to “understand” a new spell before learning it.
So the fact that Aaron could use this spell after merely reading a theory that Lily herself wasn’t sure she’d explained clearly—he was a true genius!
Lily felt a twinge of sour grapes inside: Who exactly is the one who time-traveled here, you or me?!
Aaron wore an air of nonchalance.
In his view, understanding the concept wasn’t hard—proposing the concept in the first place was the hardest and most important part!
But since Lily kept looking at him with that skeptical gaze, there was no need to burst her bubble. Keep being amazed! That’s right, your mentor is the absolute best!
“Overall, this part of your content has no major issues,” Aaron commented.
After a moment’s thought, he added, “But for easier understanding, you could add some supporting evidence. There have been folk cases where people died mysteriously while sitting by a fire at home. Some suspected dark magic at the time, but investigations turned up nothing. Now it seems they likely died from what you call gas poisoning.”
By connecting these already-observed phenomena, it would both help people understand and strengthen the argument: Lily was merely studying a pre-existing phenomenon, not dabbling in forbidden magic.
“Teacher, those cases of gas poisoning weren’t necessarily carbon dioxide poisoning,” Lily said with scientific rigor.
Burning a fire in an enclosed space could very well cause carbon monoxide poisoning—a different matter entirely. It also depended on what was being burned; other toxic substances might have been released.
“It doesn’t matter exactly which gas caused the poisoning. Just introduce the phenomenon, explain your theory, and those who are interested will naturally dig deeper.”
“Got it!” Lily didn’t dwell on it and agreed readily.
“Also, the applications of this expansion method can be further refined.”
Aaron looked at the manuscript and casually listed a few points:
“First, this spell inherently counters fire-shield defenses. No doubt that’s part of why Chris went down so quickly during the practical exam.”
“Second, according to your theory that ‘oxygen supports combustion,’ if you convert it into an Oxygen Technique and combine it with fire-attack spells, the effect would be even better.”
Fire feeding off wind—that was an application concept people already had. Now, by upgrading the wind itself, it could push fire magic to new heights.
What more could Lily say?
All she could say was: She was convinced.
She’d thought of these things too. But she had the advantage of modern knowledge and had more time to consider them, so it wasn’t surprising. Aaron, on the other hand, had arrived at these insights in a very short time!
Lily silently reminded herself:
She must be more cautious and careful from now on!
She couldn’t underestimate the mages of this world just because she had the advantage of modern information.
They were actually very smart—it’s just that the world had developed in a different direction, so they needed someone to poke through that paper-thin barrier for them. And in their own professional domains, they could run circles around her.
The freshman assessment was over, but it wasn’t time to slack off! She had to work hard and stockpile more trump cards for herself!