The next day was dedicated to preparing for our return to the castle gates. Specifically, I focused on anti-personnel tactics. While the magnetic and mana disruption fields had worked well previously, I couldn’t rely on them being effective again. Though I doubted anyone would overcome them easily, it was better to have alternative strategies ready.

After all, neither field would have any effect on close-range combatants who didn’t rely on metal gear or magic.

“Maybe this time we should try a gravity field,” I suggested.

We’d already experimented with applying gravity in fixed locations or on ourselves for flight. This time, I wanted to create a gravity field centered on myself.

Unlike magnetic or mana disruption fields, gravity could directly alter the environment. Misusing it would risk collapsing the ground, leaving craters behind.

“It’s a good idea,” Rio replied, “but isn’t it hard to control where the gravity applies?”

“That’s true. But I don’t want it to affect you, so I need a way to keep it selective.”

“If that’s the case,” Rio suggested, “why not apply equal and opposite gravity to counteract the pull near me?”

“Huh. That could work.”

Her idea made sense. Instead of manually managing the gravity field's effects around Rio, I could automate it by detecting and negating any gravitational forces in her vicinity.

“Alright, let’s test it out!”

“Sure. Let’s head outside the city for this.”

“Hmmm, if the gravity effect extends only above ground, it should work fine,” I noted.

“Agreed. No risk of collapsing the ground, so we don’t have to worry about destroying roads or bridges.”

The biggest concern—damaging infrastructure—seemed solved. This method would allow us to use the field even on elevated surfaces like bridges or second floors without incident.

“This magic is pretty powerful,” Rio commented.

“Yeah, it burns through mana like crazy, though. I guess that’s the price for this level of strength.”

The gravity field was indeed a mana guzzler, but its output was well worth it. The more mana invested, the stronger it became—simple and effective.

“And with our classmates potentially showing up, we need to be fully prepared,” I said.

“You’re right. I won’t let them look down on us again…”

Rio clenched her fist with determination. I might’ve accidentally fired her up a bit too much, but her motivation was a good sign.

“We’ll knock them all down if we have to.”

“Yeah!”

However, one earlier test of the gravity field had been disastrous. A stray idea had led to a massive explosion, creating a deep crater. I’d had to hurriedly use earth magic to fill it back in.

“Let’s move farther from the road next time,” I suggested.

“Yeah, no need to cause a panic.”

We spent the rest of the day experimenting with gravity magic until the sun began to set.

“Shu, we should head back now.”

“Huh? Oh, is it that late already?”

Glancing around, I realized the light was fading. With no streetlights outside the city, it would soon be pitch black. Though we could light the way with magic, the city gates would close soon, leaving us locked out.

“It’s inconvenient not having a proper place for experiments near town,” I grumbled.

“Overdoing it isn’t good for you either,” Rio reminded me.

“Right, right,” I replied sheepishly.

I’d once pushed myself too hard, ignoring my daily schedule. Rio had scolded me then, comparing me to my mentor. The memory stung—surely I wasn’t that bad... probably.

“Anyway, let’s head back,” I said.

Using earth magic, I smoothed over the uneven ground left from our tests, ensuring no trace of our experiments remained. Then, we began walking back toward the city.

As we neared the road, we saw others also returning to town—adventuring parties, merchant caravans, and even a lone figure cloaked in black.

By the time the city gates came into view, a line had formed as travelers queued to enter. We joined the procession, waiting behind a merchant’s wagon, with the cloaked figure falling in behind us.

“This line is so boring,” I sighed.

As the crowd swelled, I noticed the cloaked figure moving oddly. My enhanced senses caught the rustle of movement behind us. Something felt off.

“Rio!”

A sudden surge of killing intent aimed at Rio made me act instinctively. Reaching for her, I realized pulling her toward me wouldn’t be fast enough. Instead, I shoved her aside with all my strength.

“Ahh!”

Time seemed to slow as Rio stumbled. From behind her, a thin, sharp object pierced through the air, grazing past where she had been. It struck with deadly precision, grazing her right chest.

Something long and slender emerged from her back—blood blossoming like a crimson flower.