"Lightning-type magic, perhaps?"
Reiko made her assessment after seeing the blue sparks. Since purple was a color often associated with the lightning attribute, Anne and Alectas both agreed with her conclusion.
"Lightning-type magic... or perhaps a high-voltage, high-current trap."
Back on Hourai Island, Jin watched the scene with keen interest as it was projected onto the magi-screen from Reiko via Laojun.
"If it can't be detected in advance, it might not be magic-based. For example, one could use lightning-type magic to charge a powerful capacitor or a battery and then draw from that."
As he imagined the possibilities, Jin couldn't help but smirk inwardly, thinking, That sounds like a useful idea. However, he quickly refocused on the task at hand.
"Ahem. A lightning trap... I guess we have similar ideas when it comes to defenses."
If high voltage was being applied to the floor, a barrier wouldn't be very effective. Such shields generally only extended down to where they touched the ground, leaving the contact point vulnerable.
"Shoes made of magical beast leather should provide some insulation, and I doubt Anne or Reiko would be damaged by average lightning-type magic anyway, but there's no need to take unnecessary risks—especially considering Alectas..."
Jin fell into deep thought in front of the magi-screen.
From what he could see, the high voltage was generated between the ceiling and the floor. Since it wasn't a vacuum and gases were present—and because a discharge caused by magic would be influenced by the free ether—he couldn't determine the exact voltage. However, he estimated it to be somewhere between tens of millions and hundreds of millions of volts, much like natural lightning.
"Should I short-circuit it?" Jin muttered with a mischievous grin.
"Father has made something for us, and he is sending it now," Reiko announced after receiving a communication from Laojun.
Anne had received the message as well. Incidentally, Reiko and Anne were currently unable to communicate directly with one another. However, with Laojun acting as a relay, they could converse with a time lag of less than a second. Alectas, unaware of this arrangement, remained out of the loop and looked on in confusion.
A minute later, the item arrived via the transporter.
"A mithril rod?"
It was a rod made of mithril, which possessed excellent electrical conductivity. The plan was to use it to short-circuit the floor and ceiling and see what happened. The rod was long enough to bridge the gap between the two surfaces, and a grip made of insulating material was attached to the center.
Holding the grip, Reiko touched the tilted rod to the purple floor and slowly brought it to an upright position. Once it was almost perfectly vertical, the top brushed the ceiling.
In that instant, bluish-white sparks showered the area.
The current reached hundreds of thousands of amperes, but since the discharge lasted for less than a second, the mithril rod withstood the load even as it glowed red with heat.
"It seems lightning magic is no longer being generated."
Reiko spat another sphere from her mouth. Seeing it roll across the floor this time without incident, it appeared the magi-device responsible for the trap had been fried by the overload. Even so, Reiko stepped onto the floor first as a precaution. Nothing happened.
"It is safe now. Please, come across."
Thus, amidst the drifting scent of ozone, the high-voltage trap was neutralized. The purple section spanned about three meters before returning to the same gray as the rest of the corridor. Then, the passage turned to the left.
"Please stop."
At Reiko's voice, Anne and Alectas came to a halt. In that same moment, the floor immediately in front of Reiko vanished.
"A pitfall. I knew there was a space beneath the floor due to the reverberations. Such traps are meaningless if I use 'Sonar' to search more accurately."
The hole was approximately five meters wide—a distance Reiko and the others could easily leap across.
"Big Sister, there might be another trap waiting on the other side," Anne warned.
The tactic of taking advantage of the carelessness that follows the relief of avoiding one trap was a common one.
"You are right. Let us be careful."
Reiko unsheathed Touka and sliced through the metal wall, cutting out a metal plate about one meter square. She rolled it into a cylinder and threw it across the hole. The cylinder rolled away with a clattering metallic sound, but when nothing happened, she knew the landing zone was safe.
"Now, let us go. Master Alectas, can you jump across?"
"Yes, it is possible if I use physical reinforcement."
"Then, here I go."
Reiko and Anne leaped across first. Finally, Alectas made the jump, and they successfully bypassed the pitfall trap.
Beyond that, they encountered another staircase. However, this one led upward.
"...Up? Not down? Is this route a decoy?" Anne murmured.
"For now, we have no choice but to follow this path. If it comes to it, we can simply break through the floors and walls. Let us proceed."
Despite her extreme words, Reiko chose to move forward. Judging by the length of the stairs, it seemed they had returned to the floor they had previously descended from, but the area they exited into looked completely different.
First of all, the ceiling was low. Since Reiko, who was only 130 centimeters tall, barely fit, the height likely wasn't even 140 centimeters. Anne and Alectas were forced to walk hunched over, which significantly restricted their movements. The width of the passage was also narrow, measuring only about 1.5 meters.
"I believe this is what Father calls a 'dungeon.'"
Applying a suitable term from the knowledge she had received from Jin, it certainly seemed to fit the description.
"In that case, there must be another trap on this floor as well."
Just as Anne voiced her agreement, sections of the walls slid open, and metal golems about one meter tall jumped out. There were approximately a hundred of them.
"Golems this time!"
The swarm of golems attacked the group in silence. Their strength and speed were mediocre, but their numbers were overwhelming. Moreover, the low ceiling made it incredibly difficult to fight. In that regard, the one-meter-tall golems were perfectly adapted to the environment.
Only Reiko could fight properly, but even for her, it was too cramped. Whenever she tried to swing Touka, the blade would catch on the ceiling or the walls. Anne, forced into a crouch, had her hands full just protecting Alectas.
"This is quite troublesome!"
Reiko was starting to feel a flash of irritation, and Jin, watching from Hourai Island, felt the same.
『Reiko, My Lord has given his permission. Please increase to fifty percent output.』
"Understood."
At fifty percent, Reiko was comparable to a tactical-class weapon. With a single punch, golems were sent flying, taking two or three others with them. The power of her kicks put five or six golems out of commission at once. Once a small gap had been cleared around her, she made her move.
"『Induction』!"
This was Jin's original magic, which generated intense heat in metal based on the principle of electromagnetic induction.
"Anne, use your barrier to protect Master Alectas!"
"Yes, Big Sister!"
Under the influence of Induction, the remaining sixty or so enemy golems began to glow red. They soon turned orange, then yellow, and once they reached white heat, they began to melt. In an instant, the golems were reduced to a mass of molten metal.
"Since this land is so rich in ether, the effectiveness of the magic is significantly enhanced."
"B-But how are we supposed to move forward?" Alectas asked in a bewildered voice, staring at the corridor that now resembled a pool of liquid metal.
"We have no choice but to cool it down. 『Absolute Zero』."
Using magic that stripped away thermal energy, the pool of molten metal was instantly drained of its heat and solidified.
"W-What was that magic just now?!" Alectas shouted, unable to believe his eyes.
"It is our original magic," Reiko replied.
It wasn't a lie. Alectas didn't press the matter further for the time being.
After advancing about ten meters while hunched over, they turned a corner to find another staircase. This one led downward again.
"Let us go."
After a quick check for traps, Reiko stepped onto the stairs. This set of stairs seemed to descend about ten meters.
"Now then, I wonder what kind of interference we will face on this floor."
Reiko still seemed to have plenty of energy to spare, as did Anne.
"...Are we not there yet...?"
However, significant fatigue was beginning to take its toll on Alectas.