Two Months Later
"Sensei, take this, Titan Punch!"
Karin shouted as she punched toward Itachi with all her might. Although she called it Titan Punch, her body was the same size as before ( human size ), clearly not a titan....
Itachi responded with a punch of his own. The moment the two fists collided, everything within hundreds of meters around them was shattered by the shockwaves.
This was the new application Karin had learned: reducing the size of her Titan form from more than 250 meters to her usual height, but in return gaining increased speed and concentrated strength.
Blut Arterie
"Karin, this is Blut Arterie, a basic ability of a Quincy. It increases the physical strength and attack power of my attacks."
With that, Itachi performed the same punch, but this time Karin was sent flying into the next building even though Itachi used the same physical strength.
Blut Vene
"This is Blut Vene, which increases my defense to a level comparable to a Vasto Lorde Hollow...."
Itachi spoke without dodging Karin's punch as he wasn't injured even a little bit though he was launched into the sky by the kinetic force.
Heilig Bogen (Spirit Bow)
Heilig Pfeil (Spirit Arrows)
Itachi, who was still in the air because of Karin's punch, extended his left hand as a blue Reishi bow formed. With his right hand, a blue arrow appeared and rushed toward Karin.
"These are weapons made of Reishi, and this is how Quincy...well, weak Quincies fight."
BOOMM
Watching Karin punch the arrow, Itachi regretted his decision for a moment about making her a brute....there was no art in this fighting style.....no dodging, no techniques....just Hulk Style.
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One Month Later
"From now on you will spend most of your time in this arena made completely of Reishi....This will help stimulate your Quincy bloodline while we continue our combat training....You know my healing capabilities, so I won't hold back."
"Yes, Sensei."
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Six Months Later
"Karin, it's only been nine months, and your strength has really improved by a level, but....it's not enough. You have learned Reishi Manipulation, Heilig Bogen (Spirit Bow), and Heilig Pfeil (Spirit Arrows), so we will now start with Blut Vene, which your mother specialized in."
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Six Months Later
"Good. Now try to use your compressed Titan Transformation together with Blut Vene simultaneously. If you can't do that, then all this training will be wasted."
"Yes, Sensei."
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Three Months Later
"Blut Arterie can increase your attack strength....so it's the perfect buff for your Titan Transformation....Let's learn it within six months."
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Nine Months Later
"Now we will learn Reishi Weapon Creation and Sklaverei. Although you can create a bow and arrows, they aren't the perfect weapons for you. As for Sklaverei, it's the skill to dominate and absorb the surrounding Reishi, even stealing Reishi from an opponent's techniques to strengthen yourself. Both these skills are the must of a strong Quincy."
"Hai "
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One Year Later
"Now that you have learned Sklaverei and Weapon Creation....we will learn how to properly use them in combat together with Titan Transformation, as well as how to use Blut Vene and BLUT Arterie at the same time. An excellent Quincy doesn't need to switch from one form to another every moment."
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One Year Later (3 years 9 months of training)
"Now, you can defeat most Quincy elite soldiers even without using your Titan ability. So, you must learn Vollständig, the ultimate Quincy transformation, equivalent to the Bankai of those Shinigami that was explained in school yesterday."
Yes, Karin still went to school. Strength without knowledge is just brute force, so Karin didn't miss a single day of school. Her subjects included science, mathematics, and other common subjects, as well as those about Shinigami, Hollows, and Quincy.
"A Vollständig dramatically enhances a Quincy's Spiritual Pressure, Reishi control, speed, strength, durability, and Quincy techniques. But mastering it is just as difficult....Here, drink this."
Karin took the serum and drank it without another thought.
"Sensei, why don't I feel any changes?"
"That's a regeneration potion extracted from an enemy named Boros. His regeneration is the best I have ever seen, as he could regenerate even from small amounts of tissue as long as he had energy. Although this potion won't grant you that level of regeneration, it's enough.
A Quincy's lifespan is the same as a human's. Although I can extend your life by a few years, if it takes decades for you to master Vollständig....then it's over."
"I will try my best."
By now, Karin had grown into a young woman especially with the Titan potion giving her a growth spurt. She was now the same age as Ichigo, and the unwavering determination in her eyes made even Itachi nod in appreciation.
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Three Years Later
"Sensei, now I can perfectly control my Vollständig....What should we do next?"
Karin, now eighteen years old, asked Itachi, who looked as if he hadn't aged a single day, with curiosity. She now believed Itachi's words that he had been her mother's friend considering his unchanged appearance.
"Your training ends today.....Karin, do you know the greatest factor behind your current and future strength? "
Itachi, sitting on the terrace of the thirteenth floor, asked while sipping tea.
"Quincy bloodline?"
"No"
"That Titan Transformation potion?"
"No"
"Then...that regeneration potion?"
"No... Let me answer it. Your greatest strength is your will... or rather, the greatest power in this world is will itself.
From this point on, no amount of ordinary training will increase your strength by much. That is not because you've reached your limit, but because your body and bloodline have theirs.
Your will, however, has no limit.
If your determination is great enough—if your obsession is strong enough—you can perform miracles. I once knew an ordinary human who, through sheer will alone, reached the level of a Shinigami Vice-Captain.
So, after you return to the World of the Living, never forget this. Your greatest weapon isn't your Quincy bloodline or your Titan power... it's your will."
Well, Itachi wasn't just giving her chicken soup. The greatest ability of the Biceps Brachii King Serum wasn't the Titan ability but inhereting the power of will from the OPM verse. If this power is awakened, she could gain superpowers that defied logic, like Phoenix Man, who gained power simply by wearing a costume or Garou who grew stronger with each battle.
At the end of the day, Karin's potential wasn't as great as Ichigo's, who possessed additional Hollow powers, while Karin didn't. So she could only rely on her will to break her limits further.
"Yes, Itachi-sensei "
Time Freeze
Space Slash
Daikokuten
With that, Itachi waved his hand as the next instant, time froze around Karin. Before she could even realize what had happened, an invisible spatial slash cleanly severed her head. Itachi caught it before it could fall, then stored both her body and soul inside Daikokuten for future resurrection.
"I'll revive you later... Until then, rest."
Well, this was the only practical solution. Back in Mizumori while experimenting with his abilities, Itachi had discovered a flaw in Life-Death Arena. The technique recognized the death of the physical body as true death.
Against enemies capable of abandoning their bodies or existing purely as spiritual lifeforms, its effect was greatly diminished.
Well, an EX-Level ability couldn't be completely invincible.
On the other hand, this flaw could also be exploited like now. He can train one person for years while the time is paused outside and after training he can just kill the body and preserve the soul for future revival.
As for why he had never trained Sasuke or the others like this...well, there was simply no need.
"Hey, Mirror Clone... how's the progress?"
"Why are you asking when you already know the answer?" the Mirror Clone replied without looking up from the book in his hands, as thick as a baby's fist.
"Then... enough with the timepass... Let me become serious as well..."
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