After the crew agreed to train their chakra, Jon start to help them activated their chakra and open their tenketsu point. Jon then start from Zoro, he sit behind Zoro while the other surround them. Jon sigh seeing they didn't steer the ship so he make a clone to steer it. Then he put his palms on Zoro's back and run his infuse his chakra to Zoro's chakra pathway and help to move the chakra.
Surprisingly it's easier as their chakra colors are different so he can see with his sharingan where the chakra stopped by the tenketsu even if he didn't see the tenketsu itself. So he push the chakra to open the tenketsu points and after sometime Zoro finally have his chakra activated.
"Success, now we're sure that we can train the non devil fruit user. I'll tell you the training method later. But now, Luffy, you ready?"-Jon
"Yeah"-Luffy
Jon did the same with Zoro but it feels really different. While Zoro's chakra pathway is similar to him, but Luffy's pathway is different.
'Maybe because the pool is in his heart so the pathway become different too. But i still can feel it so no need to worry.'-Jon
Jon continue to open Luffy's chakra path and it took longer before he finished. It also take more energy than Zoro's as it's more complicated. Jon then ask Zoro and Luffy to use their technique and they become stronger and easier to use than before. He repeated the process to everyone else and he's exhausted mentally when he finished. He need to concentrate so it took a lot of his mental strength.
The crew start to test their new power and they feel lighter and stronger than before. Jon then give them chakra paper and show them how to use it. His chakra paper wrinkled, then wet, then fire lit make the water evaporated, then the dry paper crumble. He tells them that it is his nature transformation ability that make him can control those elements. He have Lightning, Water, Fire, and Earth. He explain the nature transformation as simple as possible so that even Luffy can understand.
After they understand, they try to do it but surprisingly the paper show no reaction at all. Jon use his sharingan and ask them to do it again. Their chakra infused the paper but it still didn't show any reaction. He can only concluded that they don't have nature transformation or their chakra is not suitable for it because their chakra is different from Shinobi. Then he tell them to stick leaves on their body but it's also failed.
Now he's sure that it's because their chakra are different. Their chakra aren't suitable for ninja arts, but it can still reinforce their body and make them stronger. When Luffy, Usopp and Chopper know this they became dejected, even the other also disapointed.
"W-well, at least you can become stronger faster now."-Jon
"But we can't walk on water."-Luffy
"Or make clones."-Usopp
"Or transform"-Chopper
'Huh? But you can transform Chopper.'-Jon
Jon just thought in his head and didn't say it out loud, he didn't want to hurt the little guy's feeling.
"Sigh, anyway i'll give you the chakra training manuals later... Ah, forget it, i will train you later and give manuals only to Chopper, Nami and Robin."-Jon
"Huh? Why's that? Are you looking down on me you red eyes?"-Sanji
"Then do you want to read the scrolls"-Jon
Jon take a stack of scroll and they shut their mouth. There's no way those idiots will read that many scrolls to learn something when they can just ask Jon. So they shut up and look away from the scroll.
"Sigh, then i will put the scroll in our bookshelf so you can read it later if you want. I will train all of you first then and you can read the scrolls or ask me if you want."-Jon
Then that day, Jon keep training them at chakra training and his clones keep their training while his one clone still steering the ship. When the day ends he became really exhausted. It's really hard to teach other people, especially Luffy, Usopp and Chopper that always playing around and can't sit still in meditation or Zoro that always sleepy, or Sanji that always simping.
Basically only Robin and Nami that really paying attention, and it make him really exhausted. Even Nami can't concentrate because there's a lot of distraction and she became angry. Teaching the crew is harder than fighting Baroque Works. Maybe it's a wrong decission to train them. But teaching is also learning, he got a lot of realisation at what he had done wrong and got new answer and inspirations from his 'student'.
At night before sleeping, Jon call Vivi again as they're new couple and still like to flirt happily everytime so they need to call everyday. He also feel bad for Vivi because he hadn't activated and train her chakra before their departure. But Vivi didn't get mad and only ask him to train her when they meet again. After he finished his call, Jon went to sleep and he supply the Yin Seal with chakra until he depleted like before.
Jon wake up and saw some of the crew start their training. He then try to teach them ninjutsu, but they can't do it at all, even the most basic. When he look at Luffy suddenly it struck him. This world resident can't use ninjutsu because their source of supernatural power is devil fruit not nature chakra transformation like Naruto World.
But they still have chakra and train it like normal energy. So they can get more power if they train their chakra. So he just train them to raise their chakra and control it, but they can't stick leaves so he just tell them to train like usual until they become exhausted because their chakra is just energy for them. So they just need to know how to spend it and they will control it eventually as it's only a buff or boost for them.
Jon himself train like yesterday, make clones to train jutsus. He and the clones always use Sharingan while training yesterday and his got an irritation so he use sharingan moderately now. While the clones train on their own, Jon decide to review Ace and Smoker technique. He can't copy it when he saw them before, now he knew why is that. Because it's not ninjutsu, not even a kekkei genkai.
Devil Fruit power is different from ninjutsu, but he can simulate it and make his ninjutsu stronger or create his own ninjutsu bases on what he saw. He also saw Crocodile's technique and it reminds him of Gaara. He have earth nature transformation now so he can simulate it. But sand is harder to control than normal soil and rock. So he need to train his earth transformation first and maybe buy Tsunagakure's Sand Jutsu manuals.
So now he just try to simulate Ace's and Smoker's technique. He's already an expert in his fire transformation afterall. He just need more jutsu but he didn't rush it, one step at a time. He try to simulate the technique for hours but he can't understand it so he gave up for now. He write the details in a scroll so he will not forget later.
'Wait, i'm so stupid. I need to train more technique first before trying to copy them. They're not ninjutsu so i can't immediately copy them.That's why i need more ninjutsu as reference. I can't try their technique now because i don't have many fire jutsu so i can't understand the principle of fire ninjutsus. So of course i can't simulate fire type devil fruit technique.'-Jon
Jon have a realisation, he forget that to make new jutsu he must have vast knowledge of ninjutsu first. This is not Ninja World so he can't use his sharingan to copy ninjutsu. Every shinobi that create their jutsus have a vast knowledge about jutsus. For example 2nd Hokage that make a lot of crazy jutsu have learned various jutsus not just ninjutsu.
Devil fruit power is not ninjutsu so he can't copy them right away, his only solution is learning more jutsu first before simulate it's power and make his own jutsu based on it. So now he will buy a bunch of low rank ninjutsu, not just S-rank. Low rank ninjutsus are faster to learn so he will have many references and understanding of their nature transformation. So now he open the shop and buy a bunch of low rank ninjutsus.
[Purchasing:
A-rank:
1. Eight Gates Released Formation
2. Chidori Current/Stream
3. Chidori Senbon
4. Chidori Sharp Spear
5. Clone Great Explosion
6. Shuriken Shadow Clone
7. Suiton: Great Shark Bullet
8. Suiton: Great Waterfall
9. Raiton: Lariat
B-rank:
1. Katon: Ash Pile Burning
2. Katon: Big Flame Bullet
3. Katon: Blast Wave Wild Dance
4. Katon: Fire Dragon Flame Bullet
5. Katon: Great Dragon Fire
6. Katon: Intelligent Hard Work
7. Katon: Phoenix Sage Flower Nail Crimson
8. Raiton: Chakra Mode
9. Raiton: Black Panther
10. Raiton: False Darkness
11. Suiton: A Thousand Feeding Sharks
12. Suiton: Exploding Water Colliding Wave
13. Suiton: Five Feeding Sharks
14. Suiton: Great Water Arm
15. Suiton: Water Dragon Bullet
16. Suiton: Water Fang Bullet
17. Suiton: Water Formation Wall
18. Suiton: Water Shark Bullet
19. Fuuton: Pressure Damage
20. Fuuton: Vacuum Great Sphere
21. Fuuton: Vacuum Serial Waves
22. Fuuton: Vacuum Sphere
23. Fuuton: Vacuum Wave
24. Doton Barrier: Earth Prison Dome of Magnificent Nothingness
25. Doton: Added-Weight Rock Technique
26. Doton: Earth Flow Divide
27. Doton: Earth Mausoleum Dumpling
28. Doton: Earth Spear
29. Doton: Earth-Style Rampart
30. Doton: Earth-Style Wall
31. Doton: Light-Weight Rock Technique
32. Doton: Opening Earth Rising Excavation
33. Doton: Rock Lodging Destruction
34. Doton: Sandwich Technique
C-rank:
1. Doton: Earth Shore Return
2. Doton: Hiding Like a Mole Jutsu
3. Doton: Subterranean Voyage
4. Doton: Tearing Earth Turning Palm
5. Doton: Underground Projection Fish Jutsu
6. Water Clone Technique
7. Water Prison Technique
8. Suiton: Gunshot
9. Suiton: Starch Syrup Capturing Field
10. Suiton: Waterfall Basin Technique
11. Suiton: Wild Bubble Wave
12. Suiton: Wild Water Wave
13. Fuuton: Gale Palm
14. Fuuton: Great Breakthrough
Purchased:
9 A-rank x 250 SP= 2250 SP
34 B-rank x 100 SP= 3400 SP
14 C-rank x 50 SP= 700 SP
Total: 6350 SP
SP: 11,162 - 6350= 4812 SP]
'Wow, so many, and there's still a lot of SP left'-Jon
Jon just buy every nature transformation ninjutsu below S-rank that sold by the system, and he already have every D-rank and below. He decide to buy all of it because he have money and didn't want to search to buy them again later when he need it. He will just buy it and learn what he want. He will make a list and group them so he can search it easier.
His only exception beside nature jutsu are Eight Gates and Shadow Clone Explosion. He will learn every Fire and Lightning release jutsu and he will choose some water and earth release jutsu that he like and maybe need it first. He even buy Wind ninjutsus to prepare when he got wind nature transformation or if not then he will train it.
He know that chakra transformation can be trained because 3rd Hokage and Orochimaru had done it. Even tough it will not be as strong as his original affinity but it will be good enough. He can also learn Rasenshuriken afterall.
There's still many more jutsu that he want to buy, but he decide to buy these first. There's still Genjutsu, Fuinjutsu, or Medical Jutsu that he also want to learn. Basically he want to learn everything. There's no way a Naruto fan like him will let even a single jutsu left unlearned if he can. But he need to train what he need first before train the others.
Beside the other jutsus are expensive. He had bought Fuinjutsu basic manual that has some basic seal like caligraphy, storage and paper bomb. But it's price is 500 SP, just like S-rank ninjutsu. So the more advanced technique will be more expensive. Fuinjutsu is very valuable and Fuinjutsu master is very dangerous. That's why Uzushiogakure, Uzumaki's Village is being exterminated as other village is afraid of their fuinjutsu.
He had decide what jutsus he'll learn first. He will learn lightning chakra mode first as it's very useful. Just look at 3rd Raikage, he become really fast and strong that make him can fight hachibi alone. After that he will train all Chidori type and Fire Release. But he will only train them after he mastered the one that he trained before. He didn't want to use a half-baked jutsu like before when he only train for one night and push himself to the limit.
Thus, Jon's Mad Training has begun, but he didn't forget to have fun too.