The number of electric shocks we had endured had reached into the triple digits. But on the final attempt of the day, we finally cleared the objective. We successfully protected Ririka-san, identified the infiltrators, and neutralized them. After retrieving the marker from the summit, we descended at a leisurely pace. I proudly reported our success to Genya-san, who was sitting in his usual folding chair and sipping tea.
"How was that? We cleared it without a single hit, Genya-san."
"Hmm. Returning unscathed with half the time limit remaining... Not bad, I suppose."
"Just... not bad?"
"This task was little more than a warm-up, after all."
Wait, a warm-up?
As the three of us stood there in shock, Genya-san stood up and turned to Ririka-san.
"Ririka, what was your impression of them during the exercise?"
"I believe they’ve grasped the basics. They are now capable of predicting attacks and identifying potential ambush spots. Their feints to draw out the infiltrators were quite skillful as well."
"I see. Then it should be fine to move on to the next stage."
"Yes."
...Next stage?
While we tilted our heads in confusion, Genya-san looked at us, his eyes narrowing slightly as he made his proclamation.
"Very well. Starting tomorrow, we shall move your training to Phase 2. In the next stage, we will be incorporating traps. You must navigate both the infiltrators and the traps while meeting the same conditions as Phase 1—clear the exercise unscathed within one hour."
A collective grimace broke out across our faces. A large part of why we had cleared the exercise this time was that we could focus entirely on watching for infiltrators. If traps were added to the mix...
"Traps too, huh..."
"Indeed. The training until now has been strictly limited to withstanding attacks from crude infiltrators who don’t use subtle methods like traps."
"Crude, sir?"
"Anyone truly intent on attacking a protection target would use several layers of diversions to draw the guards’ attention away before striking. You’ve seen scenes in dramas or movies where an explosion is used as a distraction before the actual hit, haven't you? It’s like that."
"...I see."
Genya-san was right. It was highly unlikely that someone would attack a heavily guarded target without some kind of diversion. That meant the training we had been doing really was just a warm-up.
I let out a heavy sigh at the thought.
"Anyway, that’s the situation. Do your best in tomorrow’s training."
"...Yes, sir."
Our postures slumped and our expressions grew weary as we gave Genya-san a weak, brief reply. Ririka-san watched us with a small, wry smile.
After Muroi-san drove me home and I washed off the day's sweat in the bath, I sat down for dinner with my family. My mind was so occupied by the thought of tomorrow's training that my chopsticks were barely moving. Mika noticed and spoke up.
"You look really wiped out, Onii-chan. Are you okay?"
"Yeah. I’m fine."
"You don't look fine... What kind of training are you guys even doing? You said you were mountain climbing, but with your current levels, I didn't think a day trip up a mountain would tire you out this much."
She had a point. As Mika said, if it were just a normal hike, even a trip up Mount Fuji wouldn't have exhausted me this much. However, this was more mental fatigue than physical.
"We’re playing a game of hide-and-seek while we climb," I said.
"...What does that even mean?"
Mika gave me a suspicious look. I wasn't technically lying. I just didn't want to explain the details because if Mom or Dad heard the specifics of the training, they’d probably put a stop to it.
I decided to change the subject before she could press me further.
"...How’s your training going, Mika? Is Juzo-san putting you through the wringer?"
"...Yeah."
The moment I asked about her training, Mika’s energy vanished, replaced by a gloomy aura.
...What happened?
"Did you get hurt? I have a stock of recovery potions if you need one."
"No, I’m not hurt. It’s just... today, Saori-chan and I were in front of Juzo-san again, doing nothing but practice swings with wooden spears until we were completely out of breath..."
Practice swings? That sounded normal enough. Why was she so depressed about it?
"It’s been almost ten days since we started, and all we’ve done is swing our weapons. I want to try other things too..."
Mika grumbled about the training regimen with clear dissatisfaction. Ah, so that was it. Doing nothing but practice swings for ten days would definitely get boring. We had felt the same way when we first started.
...But still.
"I suppose you're right. Doing nothing but repetitive swings can be tedious."
"Right? So, Onii-chan, you should tell him—"
Since I seemed to agree with her, Mika’s face lit up with a hopeful, pleading look. I held up my left hand to cut her off.
"But Juzo-san has a very good reason for making you do those swings so thoroughly."
"...A good reason?"
"Yeah. Didn't Juzo-san explain it to you?"
I wondered if Juzo-san had forgotten to explain the purpose of the training. If they understood the reason, they probably wouldn't be so frustrated.
"He told us we'll get hurt if we don't swing with the proper form, but..."
"...Anything else?"
"That’s all he said."
Juzo-san, you’re being way too taciturn, I thought. You aren't conveying the purpose of these swings at all.
I let out a sigh and decided to provide Mika with the missing context.
"Listen, Mika. Practicing with the correct form is meant to engrain movements into your body that put the least amount of strain on it when you use a weapon."
"Least amount of strain?"
Mika tilted her head, clearly not grasping the concept. I suppose it’s hard to understand until you’ve experienced real combat and felt the difference.
"Fighting with a weapon puts a massive burden on your body, even if you know the proper form. If you use a self-taught style, that burden increases exponentially. You’ll overwork your body and become much more prone to injury. You follow me so far?"
"Yeah."
"And a higher physical burden means you’ll burn through your stamina much faster."
"Oh!"
Mika let out a cry of realization.
"You tire yourself out quickly, and the more you fight, the more that strain accumulates, making you easier to injure. Those are just the most obvious disadvantages of not learning the proper form."
"..."
There were plenty of other downsides too. In our case, we had used the Slime Dungeon to power-level our stats, which gave us a bit of a buffer. But for Mika and Saori, who were going to challenge dungeons without that safety net, a slight difference in exhaustion could be a life-or-death matter.
Mind you, even for us, not knowing the proper form had caused so much stress to accumulate in our weapons that they had to be reforged. My wallet still hadn't recovered from that disaster.
"Also, it takes much longer to fix a bad habit than it does to learn the right way from the start. It's better to repeat those swings now until the correct form is second nature. Juzo-san corrects you when your form slips, right?"
"Yeah. Every few swings, he gives me really specific corrections."
He was being quite thorough, then. I’d have to make sure to thank Juzo-san properly next time.
"So, that’s why you need to listen to him and keep practicing. If you neglect the basics, you’ll be the one crying later."
"Okay. I understand."
Mika seemed satisfied with my explanation, and the gloom around her lifted. I was glad she took it to heart. I’d probably have to explain it to Saori-chan soon as well.
"Still, I didn't realize there was such a difference between an orthodox style and a self-taught one."
"If you train yourself, you eventually have to retrain your entire body structure to compensate for the flaws. 'Self-taught' might sound cool, but it lacks the foundation of centuries of knowledge. A few geniuses might make it work, but the vast majority of people just end up failing."
Techniques developed by geniuses on life-or-death battlefields and refined over generations were hard to beat with a style someone just made up on the fly.
As Mika and I talked, Mom decided to join the conversation.
"You two? It’s fine to talk about dungeons, but how are your studies? If I recall correctly, your midterms start at the end of next week. Are you prepared?"
"Ugh!?" Mika gasped.
"Of course. I’ve been studying bit by bit. At the very least, I don't think I'll be getting any failing grades," I said calmly.
Mom sighed at our contrasting reactions.
"Well, it sounds like Daiki will be fine. But... Mika?"
"Y-Yes!"
"A student's primary duty is to study. I’m sure you understand, but if you get a failing grade in even one subject on your midterms, I won’t let you take the Armed Exploration Permit for Special Underground Structures Issuance Exam."
"What!?" Mika cried out in horror.
Mom ignored her protest and continued, "It’s only natural. If you can't even handle your schoolwork, you shouldn't have time for other distractions. If you don't like it, then prove to me that you can balance your studies with your explorer activities."
"...Yes, ma'am."
"That was a very weak reply... I hope you'll be alright."
Seeing Mika looking so dejected, Mom put a hand to her cheek with a worried expression. I wondered if I should offer to help. Just as the thought crossed my mind, Mika turned to me with a desperate look.
"Hey... Onii-chan? Could you help me study?"
"I don't mind helping, but I have my own exams to worry about, so I can't be at your beck and call. Is that okay?"
"Yeah! Just having you help at all is a godsend!"
Mika threw her hands up in joy, looking like she’d just been saved from the brink of disaster. But Mom’s sharp eyes caught her immediately.
"It’s bad manners to wave your hands around while you’re holding chopsticks, Mika."
"Sorry."
"Honestly... but are you sure, Daiki? Can you help her and still have enough time for your own test preparations?"
"Yeah, it’s fine. I’m using my time after school and on weekends for explorer training, but I’m prioritizing my other free time for studying."
Mom’s concern was reasonable, but I made sure to review what I learned in class during my breaks at school and study before bed. The individual sessions might be short, but added together, I was getting several hours in every day.
"I see. If you say you’re fine, then so be it. However, if you get a failing grade this time, I’ll have you stop your explorer activities as well."
"What!? Onii-chan too!?"
"Of course. You understand, right, Daiki?"
"Yeah. I know."
Mika protested, but Mom gave me a firm, pointed look. Since Mika's permission to be an explorer was contingent on being under my supervision, if I was forced to stop, her trips to the dungeon would be indefinitely postponed as well. We both had to pass, or her debut wouldn't happen.
"Mika? If you rely on your brother too much, you might cause him to fail."
"Ugh!?"
"Before you complain, you should study regularly like your brother so you can pass on your own merit."
"...Yes, ma'am."
Mika gave a reluctant, weak reply. She had studied hard for her entrance exams, but she was fundamentally the type to cram at the last minute. Consistent, daily effort just wasn't in her nature.
"Anyway, that’s enough talk. Finish your dinner before it gets completely cold."
"Ah, right. Sorry."
"...Okay."
Prompted by Mom, we turned back to our meals. The food had indeed cooled down quite a bit. We had talked for a while. We finished the rest of our food in silence.
Thank you for the meal.
Once dinner was over, I decided to start helping Mika right away.
"Mika, let’s get started."
"...Okay. Please."
I led a slightly reluctant Mika to her room, bringing my own study materials along.