A couple of days later, the time for training with Tsunade finally came. Kuro had thought they would need to go to the Senju clan grounds, but the chosen training field was in a secluded corner of Konoha. As Nawaki later explained, this was due to the constant destruction left behind after Tsunade's training.
A spacious clearing with a couple of wooden dummies and hanging targets made it perfect for intensive training. Nara and the younger Senju arrived first. Nawaki looked excited, but in Kuro's eyes there was clear skepticism — he still wasn't sure how willing Tsunade truly was to train him.
But as soon as she appeared, all doubts vanished. A beautiful woman in a mesh outfit, a white shirt, and a red skirt gave them an evaluating look and snorted.
"So, you both want to train?" she asked, crossing her arms over her chest.
"Yes!" Nawaki nodded enthusiastically.
Kuro only nodded silently, observing her closely.
"Strange. I've worked with members of your clan before, and let me say, I didn't notice much enthusiasm from them," the future Hokage remarked.
"I'm something of an exception."
"Good. I won't tolerate laziness. First, let's see what you're capable of." Tsunade smirked and added, "You should've grown at least a little while I was gone, little brother."
"What?! I'll catch up to you soon, just wait!"
"Sure. Attack me together."
Nawaki jerked his head up and took a fighting stance. Kuro, on the other hand, looked completely calm — as if he wasn't bothered at all by the idea of fighting a legendary shinobi. In fact, he was intrigued. He didn't plan to show all his cards, but comparing his current level to someone like Tsunade was far too tempting.
"Begin," Senju said with a hint of challenge.
Nawaki rushed forward first. His strikes were fast and strong, but far too predictable. Tsunade dodged them effortlessly, as if teasing him.
Nara didn't hurry. He watched her movements attentively, understanding that a straightforward attack would be pointless.
When Nawaki made another lunge, Kuro used the opening to form hand signs and performed the Raging Wave Technique. Water burst from his mouth like a waterfall, intending to wash the opponent away. Naturally, Tsunade easily dodged, but Nara appeared behind her along with his water clone. The attempt to strike resulted only in an approving smile from the woman.
Before Kuro's kunai could reach the target, Senju spun sharply, her hand shooting toward his abdomen with lightning speed. Kuro barely managed to use the Substitution Technique, but his clone wasn't so lucky — it burst instantly, collapsing back into water.
"Fast… and she's clearly holding back. I've never seen anyone surpass me this much in physical ability."
"Don't think you can catch me off guard, boy," Tsunade chuckled.
Kuro only nodded, but a spark of excitement lit up in his eyes.
For nearly ten minutes he and Nawaki tried again and again to land even a single hit on Tsunade, but without much success. At one moment, completely immersed in the fight, Kuro almost unleashed a slash on the Senju princess. Fortunately, he stopped himself just in time, but his hesitation cost him — a casual swing from Tsunade sent him flying, nearly breaking a couple of ribs.
"What was that bloodlust!? That brat was clearly about to do something dangerous…" the thought flashed through Tsunade's mind.
"All right, enough warm-up. Let's see how durable you are," she said, stepping back. "Run around the field until I say 'stop'. And if anyone slows down — they'll get a 'motivating' smack."
Nawaki groaned but stood up and obeyed. Kuro winced slightly from the pain, but also began running. And so their training under the future Legendary Sannin began. And as Nara understood within minutes — it definitely wouldn't be easy.
The Senju princess watched the two children as they completed dozens of laps around the training field. Nawaki, though constantly complaining about the exhausting run, kept moving forward. He really had grown stronger lately — training with Shintaro and this boy had paid off. His speed and strength had increased, but he still spent his chakra too wastefully. Despite his large reserves, any complex combination of techniques quickly drained him, which could be fatal in a real fight.
But Kuro Nara… this boy truly surprised her. A year ago her brother had mentioned a genius in his class who could match Mikoto Uchiha, but from what she saw now, he was at least at chunin level. His proficiency with water techniques, massive chakra reserves, and attention to detail were impressive. His chakra control was quite good, especially for his age, yet something in him felt stagnant. It seemed Nara didn't always know how to properly use his strength, acting on intuition instead. Particularly strange for someone from his clan.
"If he learns to properly focus chakra in his body and apply it in close combat, he could become a real monster. What an interesting child…" Tsunade thought, turning her attention back to them.
When she noticed Nawaki's breathing become heavy and Kuro beginning to wince slightly from a stitch in his side, she finally gave the command:
"Enough!" Her firm voice instantly made both boys slow down and stop. Nara straightened, trying not to show discomfort, while Nawaki was already breathing heavily and covered in sweat.
Tsunade approached them and used the Mystical Palm Technique to heal their minor injuries. Then she crossed her arms and examined them closely.
"You both have great potential," she began, looking directly at Kuro. "You have massive chakra reserves and good control, but you're not using it to full capacity. If you learn to concentrate it in your body and direct it properly during battle, you'll become much stronger."
She shifted her gaze to her brother.
"And you, Nawaki — not bad, but your carelessness with chakra control is catastrophic. Despite your large reserves, wasting so much chakra is a crime. In a prolonged fight, you'll run out of strength when you need it most."
Tsunade stepped forward and clapped her hands.
"Well then, let's begin."
The Senju princess quickly formed a hand sign, and a shadow clone appeared beside her. The real Tsunade turned to Nawaki and gestured toward a nearby stream.
"You're with me. We'll work on water-walking," she ordered. "And you," the clone pointed at Kuro, "come with me."
After splitting up, they headed in different directions. Kuro and Tsunade's clone approached several massive boulders at the edge of the clearing. The woman slowly raised her hand, focused chakra, and struck lightly. The boulder exploded into hundreds of small fragments. Even knowing about her strength, Kuro's eyes widened. Seeing it in person was far more impressive than in the anime.
"It's all about chakra concentration," Senju explained. "You already know how to keep it in your feet to walk on trees — and most likely on water as well, right?"
"Yes, I learned recently."
"Good. The principle is the same, but now you concentrate it in your fist and release it at the last moment. If you do everything correctly, you can greatly increase the power of your strike."
Kuro nodded, listening carefully. He focused, trying to repeat the process, but his first punch didn't even leave a dent on the stone. However, this was exactly the result Tsunade expected.
"Continue," she said curtly.
While Nawaki practiced water-walking with the original, Kuro repeatedly trained his strikes on the boulders, learning proper chakra control in his fists. Thus their days of training passed. They practiced nonstop, improving their physical strength and technique.
Weeks after the start of intensive training, Kuro brought his grandfather the confirmation of his Academy achievements. As expected, he ranked first in his class. As a reward, the old man taught him the Shadow Clone Technique. It turned out to be much easier to master than he anticipated. Naruto learned it with a single glance, while Nara needed a full day.
Naturally, the first thing Kuro tested was his limit. He created two clones, then five, ten, and finally fifteen — but after they dispersed, he felt a slight headache from the sudden flow of information. It seemed he could make more, but it might lead to serious consequences. In the future, however, this issue could be solved with Reverse Cursed Technique.
Thus passed his break before the start of his third year of training. Tsunade stayed in the village a little over a month, but during that time she greatly helped Nara grow stronger. Of course, his punch hadn't reached her level yet, but he could already break off chunks of stone.
Right before classes resumed, Kuro ran into Minato, who seemed to be specifically looking for him — and looked unusually serious.
"Good morning, Kuro. I'd like to ask you for a favor."