Chapter 498 – Lecture on Underwater Magic

I immediately decided to begin a lecture on effective magic use underwater while continuing to monitor the sea area. First would be fire magic, starting with underwater combat techniques using explosions.

I created a stone wall inside a floating water sphere.

Then—when I released a directional explosion, the stone wall was crushed. Ashley, Claudia, Rosemary, then Princess Stephania, Princess Adriana, Old Sigmund, Valentina, Forset… their eyes all went wide.

The more knowledgeable someone was about magic, the stranger this would appear. There was a discrepancy between the rank of the deployed magic circle and the destructive power one would expect from the explosion, not to mention that I wasn’t using circulation.

“When you create sudden pressure like an explosion underwater, bubbles form. By utilizing the instantaneous expansion and contraction of those bubbles and arranging the right conditions, you can generate a powerful shockwave underwater… that’s the principle. By properly controlling fire magic explosions, they can serve as quite effective attack methods even underwater.”

Simple explosions certainly have their effect too… but by applying and controlling them, you can make the power even stronger. The destructive force produced by this shockwave, called Bubble Jet, is more powerful than simply hitting with a plain explosion.

“…Fascinating,” said Old Sigmund, stroking his beard as he observed the destroyed stone wall. “Some of my shrimp companions can release shockwaves using the same principle. Though they don’t use explosions.”

“Oh?”

I explained about pistol shrimp, which can close their claws to apply sudden pressure to water, releasing shockwaves as projectile weapons. The fact that they stun their prey with shockwaves to capture them sounds like something out of a joke.

Anyway, this means that bubble jet shockwaves can be created through other methods besides fire magic.

For me too… whether it’s the pistol shrimp story or shockwaves through applied spell formulas, this is knowledge I gained from BFO.

There were players who researched how to apply explosive spell formulas to use bubble jets for attacks. As a result, it became firmly established as an underwater attack technique… but in any case, it feels like a magic specialized for underwater use.

Apparently, the developers had anticipated that magic tools like underwater mines would be created from the beginning and incorporated it as a specification. While the developers who included hidden specs are something else, the players who reproduced it through research without any hints are equally impressive…

Anyway, since it exists, we should benefit from it. Princess Adriana doesn’t fight on the front lines, but if she’s going to be fighting underwater, it shouldn’t hurt for her to learn this.

Similarly, I went over the characteristics of lightning magic and other warnings. Since we’re heading toward things like magic light water veins, I’ve taught the party members to some extent, but this point still requires caution.

If you discharge electricity underwater, you need to maintain strict control over the lightning even after releasing it. Because there’s danger of yourself or your allies getting shocked.

For things like Sheila’s Thunder Gauntlet, being a magic tool means it’s better to avoid using it underwater. On the other hand, Eclair, Marlene’s familiar, apparently has no problem conducting electricity through herself and can discharge electricity underwater without issues. Though that comes with the condition of not involving allies.

Also, since things like chlorine are generated, you need to be careful about that when using large-scale lightning magic.

And so I explained various things about magic that works effectively underwater and magic that requires caution.

“As for major defensive issues… it would be opponents who use water magic as an attack method.”

This is relatively high risk. Because being in water makes the trajectory of techniques that would normally be visible on land become invisible.

“What should we do in that case?” Charlotte tilted her head.

“Depending on the power of the magic they’re using, the opponent will need corresponding charging time or magic circles. If you sense danger, defending with shields is the basic approach. If they use a lot of chantless magic, keeping your distance makes it easier to handle.”

“Ah… could that be why you brought those conical shield magic tools?”

“Yeah. They’re better suited for defending against water magic than regular shields.”

Originally they were for riding wyverns to reduce air resistance and charge at opponents, but they can also be used to deflect powerful water magic attacks controlled by magic.

Since there were several made for the Demon-Slaying Knight Order, I brought them along this time.

“In Ashley’s case, you might be able to neutralize the opponent’s techniques by controlling the water movement around yourself.”

“It seems like I just need to make the control range wider.”

“Yeah, that’s right.”

I nodded at Ashley’s response. She’s quite adept at this area, being accustomed to using water magic.

“What about earth magic?” asked Princess Stephania.

“If it has proper strength and density, there’s no problem. For example, magic like Corulis’s Crystal Bullet. Ice magic is similar too. Conversely, you can also diffuse mud to use as smoke screens or to blind opponents.”

“I see…”

Overall, earth magic might be in the easy-to-use category.

Wind magic gets interfered with by water, but techniques with greater power can be used with a similar feel. Though I feel it might be better to simply adjust and control things with water magic. Some sound-related wind magic has extended range or increased power, so the compatibility isn’t bad.

Normally, wind magic would be essential for activity underwater too. In that sense, it plays a supporting role underwater. If you supply oxygen, you can even create fire underwater.

Since it attenuates easily in water, there might be issues with effective range. But that’s partially compensated for by Marl’s Blessing.

Marl said there were no advantages or disadvantages, but that was for close combat. In ranged shooting battles, it will basically work to our advantage.

“What about light and dark magic?”

Rosemary asked while showing a somewhat thoughtful expression.

Both of these have many techniques with special effects.

“Techniques with effects like purification or curses aren’t particularly affected. Though light magic that utilizes heat will have reduced power. Dark magic might actually have good compatibility.”

“Hmm. For me, it seems my combat power won’t fluctuate much. That’s reassuring.”

“Yeah, I think so. With the blessing too, you should be able to use various things effectively.”

Rosemary’s specialty is dark magic anyway. So it can be said to be a category with relatively little impact.

To summarize… when using magic underwater, water magic is indeed the best. Next would be those with little impact, and those with synergistic effects that increase power. As for fire magic… while limited, there are usable techniques with high power.

“After this, it would be good to do practical training on countermeasures against water magic. For dealing with opponents who disguise their magic circles or use chantless magic… the basics are the same. Keeping in mind that things are invisible underwater, deploying shields early is important.”

“Understood.”

As Grace said this, Marlene also nodded seriously with a earnest expression.

Disguised magic circles show awkwardness or give off a strange feeling, and since they generally involve extra steps compared to normal magic circles, there’s a difference in activation speed.

In that case, it’s good to disrupt and aggressively attack to disturb their control.

For chantless magic, underwater you can either keep your distance to take advantage of power attenuation through water, or anticipate the lack of power and fortify your defense for a forceful breakthrough. Either way, since Great Magic won’t be coming at you, you can deal with it calmly.

I’ve already communicated these countermeasures against magician types to the party members and we train regularly. As for martial arts, thanks to Marl’s Blessing there are no problems, but there are still unique aspects so it’s necessary to get sufficiently accustomed to them.

“Well… for today, let’s wait here until sunset, and after we return to Aianos, we can do some mock battles or something.”

Everyone nodded at my words.

Weltes and the others’ movements should be informative too, and training with Aqua Golems should help us identify the discomfort when water magic is used against us.

Until the Sea King’s subordinates arrive… probably just a few more days, right? I want to train thoroughly and be prepared when that time comes.