Under normal circumstances, Natsume-san's wind blades were, at most, comparable to a stream of low-speed gas.
But by creating a pressurized air pump and narrowing the nozzle's outlet, she could make those blades carry kinetic energy rivaling that of a bullet.
The problem was, wind blades in that state tended to break apart mid-air—they were tricky to control, their effective range was unpredictable, and they were even less practical than water jets.
As those very wind blades were effortlessly blocked by a flash of fire, the handle of the tightly shut door instantly melted under intense heat, and the various detection devices on it were destroyed in the blink of an eye.
The moment they broke down, alarm sirens blared out in waves.
Strangely enough, the surroundings remained dead silent, as though everyone had simply vanished.
The brief skirmish in the hallway shattered what little peace they had.
Natsume-san, now fully aware she was inside Judgment Branch 177's office, immediately activated a certain combat protocol in her mind.
Ever since her last fight with that magician, she'd realized how outmatched she was in every way. So one night, while lying in bed, it suddenly hit her—a way to counter him.
She glanced toward Misaka-senpai and saw that everyone else seemed relatively calm.
All they had to do now was wait for Shirai-san to return and escort Komoe-sensei and Saten-san to safety.
But Natsume-san had no intention of retreating. She needed to find out why these magicians had attacked Meigo-senpai—it was important for all of them.
She'd just been discussing this with Shirai-san earlier, and now the answer had literally shown up at their doorstep.
Natsume-san wasn't about to let this chance slip, and it looked like Misaka-senpai felt the same.
Outside the building, Natsume-san dismantled the original air pressure pump and gathered a massive amount of gas, forming a huge pneumatic cannon around the structure.
What shot out of this cannon wasn't a wind blade, but a wide-range, high-speed shockwave of air—its velocity instantly breaking the sound barrier.
By continuously increasing the pressure inside the cannon, she figured it would be more than enough to handle that flame magician's fire.
After all, pneumatic cannons were nicknamed "blockage clearers"—they were incredibly useful tools.
No matter how scorching the flames the enemy hurled her way, she could just blow them all away. That was Natsume-san's current strategy.
Her mind raced through the plan, and she acted accordingly.
The cannon's muzzle aimed through the window straight at the magicians in the hallway—the glass already shattered earlier by a certain bun-haired girl during the wind blade volley.
Damaging public property wasn't Natsume-san's intention; she just tended to overlook such details once a fight broke out.
"Master, look outside the window."
One of the magical girls tugged at Stiyl's sleeve, drawing his attention to the translucent sphere glowing with intense heat outside the window, growing brighter by the second.
To produce a shockwave of sufficient force, a certain bun-haired girl relentlessly compressed the air, raising the internal pressure higher and higher.
As the air grew denser, intense friction generated immense heat, causing the temperature inside to skyrocket.
Her original plan was to keep compressing the air to build up kinetic energy, but things had escalated beyond Natsume-san's expectations.
In no time, the sphere's temperature soared past a thousand degrees Celsius, far exceeding her usual control limits.
Waves of intense heat seeped into Judgment Branch 177 through every opening. Combined with the thermal map forming in her mind, Natsume-san realized things were getting out of hand.
What's more, friction generated electrical currents.
As the internal temperature and pressure climbed, her air cannon suddenly crackled with arcs of electricity, surges of current abruptly cutting power to the entire building.
It was on the verge of reaching plasma temperatures—ionizing the air into plasma and turning the sphere into a ball of electrified gas.
'Spiraling Sphere?'
Natsume-san sensed the superheated orb and murmured under her breath.
If she switched from direct compression to rotational compression, she felt she could literally form a Spiraling Sphere with her own hands.
"Natsume-san, what's happening outside?"
Komoe-sensei and the others had already been evacuated by Shirai-san, who'd returned just in time. Misaka-senpai let out a sigh of relief before asking urgently.
"My calculation formula… seems to have a problem."
Her cheeks flushed slightly as Natsume-san hesitated to explain.
For an esper of her level, such a major flaw in her personal formula was almost unheard of.
It was like being a straight-A student who suddenly scores a 59 on an exam—utterly embarrassing.
Natsume-san was, in a way, starting to feel the weight of an idol's reputation.
"Wait, no—the formula's fine. I think I just… overcalculated."
She reviewed the formula again and found it as sound as all her others. The only issue was the sheer number of iterative calculations.
By concentrating all the air into a single point and compressing it at an extreme ratio, the internal friction had generated an ultra-high-temperature thermal sphere.
In a way, it indirectly compensated for a certain bun-head's inability to produce extreme heat on her own.
Looked at that way, this wasn't a failure at all—it was a stroke of genius. She'd just developed a new technique.
The thought inexplicably lifted Natsume-san's spirits.
"Master, what should we do?"
Stiyl had blocked all the heat so far, but the other magical girls were beginning to panic.
They weren't exactly battle-hardened—nowhere near as unflappable as a certain troublesome Level 5.
"To develop a move like this so quickly…"
Stiyl furrowed his brow, sensing something wasn't right.
His memories of their last fight were still fresh. Although this Level 5's ability was troublesome, it hadn't posed any real threat to him. Her tracking methods were what left the deepest impression.
But now, this thermal sphere had already jumped from over a thousand degrees to two thousand and was still climbing. The suppression he once held over this Level 5 had completely reversed.
What surprised him, though, was that the blazing fireball suddenly burst apart.
With a violent deflagration, most of the gas was forcibly expelled in the opposite direction—but it still blew out one entire wall of the small building.
"Solved it. Good thing nothing worse happened."
Natsume-san promptly cut off her computational power, channeling the gas harmlessly outward, and inwardly relaxed.
She had a feeling that if she hadn't stopped, things could've gone very wrong.
Even though that high-temperature sphere was still her own ability, until she perfected it, Natsume-san had no intention of casually using such an unpredictable move again.
--+--
T/N: I have a Patreon! While it may seem empty as of now, webnovel will get 3 Chapters Every Day, and advanced chapters will be uploaded on Patreon.
It may not seem worth it now, but maybe in the future. Who knows!
[email protected]/AspenTL
If you guys wanna check it out.