To be precise, it was Hashirama's Sage Mode. Given Hashirama's personality, he naturally would not hide anything in this regard, so the training method for Sage Mode was very likely passed down as well.
So if possible, Furina still preferred to learn Hashirama's Sage Mode. Although Mount Myoboku could also teach it, she really had no good impression of that pretentious Great Toad Sage.
As for why she wanted to learn Sage Mode, that was even simpler. As her enemies continued to grow stronger, ordinary ninjutsu power was gradually becoming insufficient.
Especially her main affinity, Water Release - aside from a small handful of techniques, most were basically useless now. The enhancement from Sage Mode had become indispensable.
"Then let's set off. The village can't go without a Hokage for too long."
Seeing that Furina showed no reaction and just kept being a hazard, Jiraiya did not think too much about it. The group immediately set off on the journey to find Tsunade.
.....
"I already did exactly what the Pervy Sage told me to do. Why is this rubber ball still impossible to burst no matter what? Is there something wrong?"
On the way to find Tsunade, Jiraiya did not forget to continue instructing Naruto. And as Minato's son, Naruto naturally could not skip learning the Rasengan.
However, after breaking through the balloon stage, the subsequent, much tougher rubber ball had stumped Naruto. Even when he put in all his effort, he could only make the ball tremble violently, but exploding it was still a long way off.
"Is it really that hard? I feel like it's okay."
Hearing Naruto's complaint, Furina suddenly moved close to him. At the same time, a blue sphere slowly condensed in her hand - it was clearly the Rasengan that Naruto was training.
Since they were all traveling together and Furina was Naruto's teammate, Jiraiya naturally would not favor one over the other. Since he was teaching anyway, he might as well teach everyone at once.
And Furina was naturally more than happy about this. A ninjutsu like the Rasengan, which could grow stronger along with the user's strength, suited her tastes perfectly. She was just afraid she would end up with a ton of chakra but no techniques to use - that would really leave her stuck.
Moreover, unlike Naruto whose chakra control was affected by the Nine-Tails, thanks to her excellent control and massive chakra reserves, Furina mastered the technique in no time. She would occasionally come over to show off in front of Naruto, just like now.
[Chakra: Elite Jonin (2890/100000) → Elite Jonin (100000/100000)]
[Chakra: Kage (0/500000)]
[Affection Value: 22654]
"Furina, you again. How can you be so annoying?"
Even though this had happened many times already, facing Furina's Versailles-style bragging, Naruto still could not quite take it. So what if she learned it a few days earlier than him? He would catch up sooner or later.
"Actually, I came over because I wanted to tell you a quick training method. But you actually said you hate me. That's really depressing. Fine then, I won't bother you anymore~"
"Hey, wait!"
Seeing Furina pretend to leave, Naruto quickly called out to stop her. It was not because of any real hatred or depression. After spending so much time together, he already knew she was just teasing him and did not mean it seriously.
What he needed right now was the Rasengan he had been longing for!
"Sorry, Furina. I was wrong just now. Please tell me how I can train faster and succeed sooner."
"Ugh."
Watching Naruto who seemed to be acting spoiled, Furina almost could not hold back from kicking him flying. If you're going to act cute, can you at least turn into Naruko's appearance? This is just creepy and weird.
"Sigh. You should know that when shadow clones get dispelled after taking damage or whatever, the injuries go back to your original body, right? The same logic applies: have your shadow clones train the Rasengan too. When the clones disappear, the memories and experience will return to your original body."
"Shadow clones can be used like that?"
"Of course. Would I lie to you?"
Naruto naturally trusted Furina completely. After hearing her assurance, he immediately created a bunch of clones, resulting in a scene of a whole group of people rubbing balls together.
Seeing Naruto so excited, Furina did not say anything more and just stood to the side, waiting for his results.
"Bang!"
After creating dozens of clones and practicing together for a while, once he felt it was about right, Naruto dispelled them. After closing his eyes and sensing for a moment, he suddenly looked excitedly at Furina beside him.
"It really seems to work! But why didn't anyone tell me this back at the ninja academy? If I create this many clones every day to train together, my training speed will definitely increase a lot, right?"
"Who knows? Maybe they didn't realize it could be done that way either."
Looking at Naruto's puzzled expression, Furina could not help but feel a bit sweaty. Did he really think everyone had chakra they could squander like him? The Multiple Shadow Clone Technique was classified as a forbidden technique precisely because the chakra consumption was so huge it could endanger your life.
However, Furina did not voice any of these thoughts in the end. By now, Naruto could probably realize that his enormous chakra had something to do with the Nine-Tails, and the Nine-Tails was also the reason he had been ostracized. There was no need to bring that up at a happy moment like this.
"Hey, you guys, how's the training going? I found Tsunade's location. We can head out now."
Just as Naruto was rejoicing over his progress, Jiraiya, who had gone out to gather information, returned. Hearing his question, Naruto eagerly showed off.
"Watch this, Pervy Sage."
Under everyone's gaze, the rubber ball in Naruto's hand shook violently. Although it ultimately did not explode, anyone with eyes could see that success was not far away.
"Um, I'm still about the same as before."
After watching Naruto's demonstration, everyone turned to look at Karin, who had remained silent the whole time. Facing all the stares, Karin said somewhat embarrassedly about her own situation.
After hearing Furina's method earlier, Karin had tried it too. But compared to Naruto, the Nine-Tails Jinchuriki, even though she was from the Uzumaki clan known for chakra, she still could not compare to him at all.
The most obvious difference was that Naruto could create dozens of clones and still handle it easily, while Karin could barely manage fewer than ten clones before being completely exhausted.
Moreover, her compatibility with the Rasengan was not very good either. So despite training for so long, she had progressed very slowly and was still stuck at the rubber ball stage with no further advancement.
"Take it slow, no need to rush. You just need to master it eventually."
"Why are you looking at me? Do you need me to show you again?"
Seeing Jiraiya comfort Karin and then look toward her, Furina could not help but feel puzzled. Hadn't she already shown him her Rasengan? What else did he want?