Fukasaku!

Ryo used the summoning Justu, so a big cloud of white fog appeared. Usually, the size of the cloud is proportional with the size of the one summoned. Ryo expected something of the scale of Gamabunta or Gamaken.

"Jiraya Chan! You can summon me directly now, it seem like you Sage mode has improved greatly!" The smoke has not disappeared yet, but an old voice could be heard within it.

"Boss!" Hearing the voice in the smoke, Jiraya was shocked.

"Huh? You're not in sage mode?"

The smoke dissipated and a palm-sized green toad stood there in front of everyone.

"Fukasaku Sama! How come it's you?" Minato also went to Mount Myoboku, where he got familiar with the two great sage toads.

"Minato, this feel awkward, what's with all the respect? This one isn't that big!" Asked Kushina.

"Mount Myoboku is one of the big three unexplored Sage regions. There reside the conscious Toads. They have three elders: Gamamaru sama is the patriarch, and his two heirs who are the two great sage toads: Fukasaku sama is one of them, and he's Jiraya Sensei's trainer."

"Minato Chan! Stop whispiring." Fukasaku had centuries of training. His perception was amazing, and he could hear everything said by Minato, even though he was merely whispering.

Embarrassed, Minato scratched his head.

"Minato, who is the other elder?" Seeing that Fakasaku wasn't angry, Kushina asked Minato to finish his answer.

"It's his wife, Shima Sama."

Fukasaku's temper was much better than Shima's. It was fortunate for the bunch that the one summoned was him. It would've been a lot of trouble if Shima heard Kushina's comment about her size."

"Then Jiraya Chan, seeing how you're surprised, I can suppose that you're not the one who summoned me?"

"True, boss! This is the kid who did."

"What?!" Fukasaku was extremely confident about his perceptive abilities. But he was not aware of the existence of someone behind him.

He turned around, looked at him, then closed his eyes and tried to perceive him. But what happened surprised him.

What he perceived in Ryo's position was a block of Ice.

This was the 1st time Jiraya saw Fukasaku be so amazed. "Boss, this little devil is called Ryo Yamanaka. He is a new contractor."

"Ryo Yamanaka?" he looked well at Ryo.

"Yes, boss! Originally, I also wanted to go to Mount Myoboku to talk with you about him."

"Oh, what's the matter?"

"Here's the thing. I found out that this kid can use Jutsus that are ice related. And he was using natural energy!"

"How could this be? Ryo Chan, can you show one of those Jutsus?"

Ryo nodded and froze Water Waves he created.

As Ryo did that, Fukasaku didn't perceive that Ryo was using a Ninjutsu, he actually perceived Ryo turning into a part of nature.

Even in Sage mode, one just absorbs natural energy, merging it with physical and spiritual energy. Ryo creating the ice didn't envolve any use of Chakra.

"Jiraya Chan, where did you get this contractor from? He's able to use pure natural energy perfectly!"

"Boss, you mean that the kid didn't use Chakra at all while freezing the water?"

"That's the case." Fukasaku was positive about what he was saying.

"Well how come, Fukasaku sama, that everytime I use Ice Release, I consume a lot of Chakra?" Ryo was wondering.

"Far Chan, are there any conditions you should meet before entering this mode?" Fukasaku took a while before answering.

"Yes! I must be in a special mode, the one that's active now."

So Fukasaku nodded and carried on asking: "Than you need to learn how to maintain this mode without spending Chakra!"

"I don't need Chakra for that. Once I get into the mode, I don't spend any Chakra to maintain it. It's just that freezing requires huge amounts of it."

"Aha! So that's this case! Ryo Chan, you mode is perfect, but the problem is with you."

"Is there a problem with my use of natural energy?"

Ryo's biggest trump card was Ice. If he can solve the problem he's having with ice requiring huge amounts of Chakra, even his fights with Kushina won't so one-sidedly dominated anymore.

"It not your use of it that's the problem. Fixing your problem requires more than understanding natural energy. It is the energy that circulates in the world. In you mode you are a part of nature itself, you energy is part of nature's energy, so you can maintain this mode without consuming any more energy."

"So Fukasaku sama, why do I lose so much chakra whenever I try to freeze anything?"

"It's very simple, Ryo Chan, when you use any Ice Release Jutsu, you actually consume natural energy from close source, with the closest being yourself! When you've consumed all natural energy in your body, the flow of energy is passively supplemented with your chakra to maintain your ice mode. That's how you drain your Chakra."

With Fukasaku's interpretation, Ryo finally understood it.

When using his Ice element, Ryo was like a pool that's full of water, with 2 inlets and 2 outlets. When Ryo is in his Ice mode, it's like having one of the inlets and 1 of the outlets open. This keeps the pool full and prevents it from overflowing. For Ryo, it maintained the amount of natural energy within him stable.

Using an Ice release Jutsu opens up the second outlet within him without opening the 2nd inlet, making water (natural energy) leave his body with incredible speeds. Here, to maintain the fullness of the pool, he needs to use his reserve water source, his own Chakra! Once it's over, the pool is drained and he can't use Ice Release anymore, nor could he use normal Ninjutsu as he has no more chakra.

If he keeps on using Chakra to supplement his consumption of natural energy, even having a Biju shouldn't cut it.

"Fukasabu sama, there any solution to this problem?" Ryo asked.

"Yes, learning how to replenish natural energy consumption from the universe is the best way to..."

"Boss, do you mean to learn the Sage mode?" Jiraya also asked.

"Jiraya San please let him finish!" Ryo stared to Jiraya.

"Well, it's the same concept. But unlike other practitioners, you don't have to worry about being swallowed up by natural energy as he can become a part of nature. It's just that..."

He looked in Ryo's eyes, hesitated a bit then said: "You can never use Sage mode!"