Kuroshi Clan, Kai's House. Night.

"Haaa..."

Juro and Kai were seated while facing each other. When Kai explained what happened to Juro, he sighed.

"Listen, I know you lost most of your common sense and tact while you were away but I'm sure you know that it isn't okay to hurt a girl that much in a mock battle. You two fought like it was life and death but you obviously had more power and should have subdued her but instead used all your mana for an attack, seriously..."

"Yes..."

"Also, not to mention the fact that she's a girl, she's also the direct descendant to the duke who could literally erase you from existence with a single palm. I've also heard that the Mariko Palace is the most influential duke palace in the entire kingdom because the duke is at the peak of A-class, and not only that, he's also defeated an S-class before."

Kai's ears perked up when he heard that.

"How many S-class are in the continent?"

Juro held his chin.

"Last I've heard, there were only eleven. The S-class are the strongest power and rule the continent by meetings. They're basically the rulers of the continent."

First I've heard of it. Reo hadn't told me much about the continent since he's also been asleep for awhile.

"Anyway, Kai when are you going to start using illusion world?"

Kai tilted his head and made 'mmmmm' sounds.

"I just finished training and wouldn't really like living in the woods again for awhile so maybe in the next three months?"

Juro nodded.

"I see."

Just as Juro's words faded Kai faced the room where Erina was sleeping.

"She's awoken, I'll go talk to her."

"Yeah."

Juro waved him off and Kai headed straight for the room.

"Yo."

Erina sat up while holding her head.

"Ahhh, I've gone and done it..."

I was too riled up and unintentionally used that.

Kai stepped in the room and closed the door behind him and immediately created a sound barrier.

"So, you've already figured out some of my secrets and I've confirmed it so would you mind telling me yours now?"

Of course, Kai was referring to her silver hair. The cyan eyes were common when using the ice attribute to a certain point but Kai had never gotten silver hair, and not only that but it was also glowing fiercely. And the power she displayed when she used it actually matched about a third of Kai's mana.

"I-it was just a fluke, hahaha... alright I'll explain..."

Erina was trying to bluff her way out but Kai narrowed his eyes. She knew that she wouldn't be able to fool him.

"Alright, it's a forbidden power that boosts my strength. I only used about a fourth of it so that it wouldn't do any damage to me but the power I had gotten was still enough to destroy your attack and more."

Erina straightforwardly gave out her secret. She wouldn't be able to hide it anyway.

"I thought it was something like that, when I healed you I found that your life force was damaged."

Erina visibly twitched. She was trying to hide the fact that that was the price.

"I suggest you stop that. If you continue learning that technique, I will stop you with all of my power. And if I do, you can be certain that you won't be able to use magic ever again."

Erina was speechless.

"Well, thanks for caring about me but I have to learn it no matter what."

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Kai and Erina glared at each other for a bit.

Kai's mindset was still the same with Earth, sacrificing lives and killing people is morally wrong for him. Naturally, Erina was the same but sacrificing her life force to use this technique was something that Kai wouldn't allow.

"So, what happened to Reo?"

Erina changed the subject.

"I can call on him at anytime, he says he'll appear when I need help or if I just ask him. He was only by my side because I needed help during training but now I'm fine."

 Erina stared at Kai.

"How strong are you, really? The last attack I used was strong, even if you were hit by the edges you would've been forced to kneel from the attack and bleed but not only did that not happen, you even moved immediately. And not just that, you used 'the rest of your mana' but I doubt that's really it. Your mana reserves are too small compared to before, as if they're sealed."

Kai shrugged.

"My body right now is B-class I guess. My magic power is... I'll tell you after you tell me yours."

Erina's eyes were wide open.

"B-class body at that age... amazing. My body is only C-class because I've trained my magic power more but for some reason, I can't improve my body anymore. Then my magic power is at the peak of C-class but I felt like we had the same amount of power yet I can't help but think that's not right."

Normally, she wouldn't disclose any opf these secrets but the curiosity of finding Kai's strength was too much for Erina. Even if it was only a chance to find out, she'd take it.

"Alright, my magic power is also the peak of C-class. A bit more and I'll enter B-class but my mana reserves are... A-class, though due to some circumstances I can only use magic power enough to be qualified for C-class."

Their battle used a lot more mana than other battles at their level. Mostly, mages only attack from afar and whoever had a higher amount of power or the highest amount of mana reserves would gain victory but ice has very limited attacks without forming objects. Using [Ice Blade] for combat is a given because the user won't have to expend a lot of mana to make attacks and stick with a single weapon.

But Erina and Kai both used an amazing amount of mana by creating giant pillars, weapons, and blasts. It also takes more mana to manipulate ice that has already been released than to form it before releasing. Kai's [Ice Cage] uses a lot more mana than eight [Ice Walls].

But the pillars Erina used for the first time were larger than Kai's. And the one that was rising up was larger because it continuously expanded. Not to mention the giant ramps of ice.

Kai's magic circles were used to save mana. Kai uses a bit of mana to form them and the magic circles take mana from the surroundings and use them for spells.

"Then, what was that magic circle you had formed near the end?"

That was an entirely different concept from Kai's magic circle. Instead of taking in mana from the surroundings, it forcefully took her mana and also damaged her life force.

"I..."

Erina hesitated.

"Come on, tell me. I won't let you kill yourself if it means getting more power, I'll even train you myself if I need to."

Erina looked down and at Kai then down again.

"Haaa... Fine, I won't ask about it. But make sure to never use it unless your life depends on it, to use it in a mock battle is stupid."

No matter how mature she is, she's still a kid acting impulsively. I heard that Yoko had also let her darkness run rampant and consume her during the triennial tournament, these two are the same in that unwillingness to lose.

 "Kai, what did you do at the end? That [Blizzard] of yours, it used most of of your mana but the effects were amazing, if I didn't have ice attribute I'd probably freeze there."

Kai made a 'hmmm' sound.

"I can't really explain it well but it uses my mana to manipulate the surrounding mana and infect them, I guess? You know how the surrounding's mana is dependent on the environment? If the place is hot then the mana around is more suited for fire attribute users, like that? Well, I change all the neutral mana to my ice attribute and create phenomena with them. I basically just discharge a large amount of mana to infect the rest and that's my move. I also have a similar one with flames called [Inferno] but fire spreads a lot easier than ice."

 Erina tilted her head.

"Infect the neutral mana...?"

Kai waved his hand.

"You don't have to understand it. Reo told me before about the mana from the surroundings and I just used that to make the technique, it's difficult but since you're a genius I'd bet you can replicate it in a month or two. I'll even give you pointers about it if you like. But I have a question about that 'Noble Sword' of yours."

Erina made an 'ah' sound.

"That is a technique known by most nobles to counter other sword attacks and techniques. It's not really useful towards magical attacks but it's useful in close range fights. Nobles fight other nobles with rapiers and it started from there. It takes a lot of skill and focus to master it."

To produce an equal force to counter inertia, whoever created this sword style is worthy of praise. It isn't easy to find the amount of force behind an opponent's attack, you have to read even their most miniscule movements and their positions. Not only that, the opponent's muscle must also be observed closely.

Kai thought so.

But that means she read my movements that I've been honing for the past years that quickly...? This woman is frightening indeed.

"You should sleep here for tonight, it's already dark. You can just inform your butler hiding near us. He doesn't hear us at all but I bet he's only here to guide you."

Erina was surprised, even she hadn't sensed Yasuo.

"Alright..."

Kai left the room and went to his own after taking down the barrier.

"That was good experience, I can add some techniques to my arsenal now."

Kai had a smirk as Reo appeared beside him.

"Still, that girl improved by leaps and bounds since I last saw her. If both of you released all your trump cards, I'm not sure who would win. Back when we first met her, you would win without a doubt but now..."

Kai nodded.

"I agree, she probably improved almost as much as I did during these past years."

"Her power didn't increase too much but the amount of trump cards she holds have certainly increased. But if she were to use that technique that made her hair silver, you'd lose unless you use that technique."

"Yeah, but I can't use that now. It takes too much of my mana, last time I was lucky enough to stop it but if I execute it with a damaged or tired body, I'd probably die instantly."

"You're one to lecture her about sacrificing herself..."

"Hahaha..."