After 3 months of training, Jon finally can harden his skin with Haki. It's still colourless and unstable, but he can finally grasp it and activate it willingly. In these 3 months, he can sometime use it coincidentally, so he only need to feel it again, but it's difficult.
What make it harder for Jon, is that he always draw chakra instead of Haki. Even after Kurama block it, he still attract his chakra to draw out. Chakra also have 50% spiritual energy, so it's not strange. But that's just hindering his progress.
In contrast to his Armament, his Observation become stronger fast. Now he can cover the whole building, and feel everyone's presence. But for their intent, he still can only feel about 50 m diameters, and effectively at 25 meters. But it's already a fast progress, he has higher talent in sensing it seem.
Jon also make a lot of progress in Medical Jutsu. Maybe it's because he have high chakra control, sharingan, and Hashirama's gene. Now he can use normal Healing Jutsu and working on Mystical Palm. He have succeed using it to a fish for a few times, today he will try using it on himself.
"You look more energetic than usual, kid."-Dragon
"Yeah, i almost succeed in my new jutsu, i just need to test it later on myself."-Jon
"Ooh, what jutsu is it?"-Dragon
"Heeh, be impressed old man, it's a medical jutsu. If i succeed, i can heal injury faster, altough i can't treat illness, it will need more thorough medical study."-Jon
"Hoo, it's good, then you can help healing the wounded ones."-Dragon
"Oioioi, i'm not aiming to be a healer, it's just a supplementary skill so i won't die easily."-Jon
"I know, i mean you can help them when you have time. You need to use it often if you want to master it right?"-Dragon
"Well, yeah. Alright then."-Jon
Then they did their usual training until Jon got beaten up when they finished. Even if he can use most basic armament, but it's not enough to defend Dragon's attack. He need to use hardening that make his armament black.
Jon has improve a lot during his 3 months training. Now he use 175 kg weights in total, he can also can run normally when using them. His body's durability also increase a lot with all those beating. But with his durability increase, his beating also become longer. Now he train from morning until night, not evening.
The most notable improvement on him is his chakra. Now he have Senju's blood, and he even have Uzumaki's chain, so maybe he have Uzimaki's blood too. Senju clan & their cousin Uzumaki clan have big chakra reserve. Now his chakra grow faster than ever before. He's already a mid kage level chakra, when previously, he was only an elite jounin.
'I don't know if i will have high chakra like Hashirama if i get the cells instead of gene. But i'm sure i will not be able to grow as strong as Hashirama. The potential of his cells are good but it's not the best. I also refuse to have that corpse like pale skin or even worse, Hashirama's face, it cringe me even now.'-Jon
He need to take longer route, but he know he will gain more. Beside, he like growing stronger by himself. Hashirama's cell is like a cheat for the one who have it. Well, he use cheat too actually, to have Madara's and Hashirama's gene is a very big cheat in itself.
The system actually said to him that he will get Hashirama's regeneration ability in the future even without training. But he know that even with Hashirama's regeneration ability, he still can get injured. He also didn't know when he will get it, so it's better to prepare.
'That regeneratiom ability will only work for me. What i want is something that can help our crew, and medical jutsu is the best option. Chopper can make many medicine for illness or even poison, so i just need to treat wounds. So this medical jutsu is the best option.'-Jon
Jon also didn't train in Creation Rebirth even if he have Yin Seal. Creation rebirth didn't heal cells, but hastening cells dividing process. It has a drawback, which is shortening user's lifespan. He didn't really want to live a short life. He has took 5 years with Iva's hormon injection, but after rebuilding his body, it should be fixed too. So he don't want to throw another years of his life span.
'Even Hashirama's regeneration ability must have a drawback and requirement too. My guess is his massive chakra that can make his cells have more vitality, so they can repair themselves. But even Hashirama can die too. I don't know why he die tough, but he was not die of old age, i'm sure of it.'-Jon
He stop thinking about it and concentrate on his healing. He can heal almost every part of his body, except his back. He can't touch it with his palm afterall. But Jon is satisfied with it, now he can train his ninja arts again. Some bruises on his back are not a problem.
Jon have a dinner first before he train again. Then he go to the training field and he will revise all his ninjutsu. He need to do it after 3 months of vacuum. But it seem he worried too much, he can use his ninjutsu just fine. He can even do more with his chakra reserve now.
"Alright, now that i can train like usual again, i will try to use Wood Style. System, did i get a wood affinity?"-Jon
[Not yet host]
"Hmm, why?"-Jon
[Because you have Hashirama's gene, not his cells where he already have wood kekkei genkai. Hashirama himself need years of training before he make wood release.]
"The-then, do i need years like him?"-Jon
[No host, system will not make it so hard on you. System will give you wood nature affinity after reach the requirement.]
"Ooh, what is it?"-Jon
[Raise your Earth & Water chakra mastery to 90%.]
"Hmm, it have high requirement."-Jon
Jon then stop thinking about that, and train again. He want to train many more ninjutsu, and his chakra reserve really help a lot. His Yin Seal capacity also increase and if he open his Yin Seal, he will have High Kage chakra level.
"Speaking of Yin Seal, i have Yin release as i have Uchiha blood. Now i have Senju blood, then i should have Yang release right?"-Jon
[Yes host]
'Kid come here!'-Kurama
Jon enter his mind scape after telling his clones to keep training.
"What do you want?"-Jon
"You just remind me that you have Yang release. I am only a Yin part of my real self, so even if i gather chakra, i still can't gather Yang chakra. You should know that Yin is creating form, while Yang is giving life. If you master your Yang chakra, then you will have tremendous life force. That is the reason why Hashirama can heal very fast."-Kurama
"So that's how it is, i am neglecting my Yang chakra. Why don't you tell me earlier?"-Jon have a tickmark
"I forgot, and i don't really care about it. Anyway, because you have Yang chakra, i want you to give me some of it."-Kurama
"Huh? Why?"-Jon
"To complete my power, i only have Yin chakra, and i can't gather Yang chakra. If i can gather Yang Chakra, my power will increase a lot. You will also benefitted from my lifeforce. Even now you can heal faster, imagine if i have Yang chakra too."-Kurama
"I can just increase my Yang chakra too."-Jon tilt his head
"Will a human's lifeforce surpassing that of Tailed Beast? You may get serious injury that you can't heal. Also, what if your chakra depleted? Tch, and here i am being such a kind hearted guy."-Kurama have a pissed off expression
"Alright alright, damn, you don't need to act like a teen in puberty."-Jon
Jon then approach Kurama and he sit on Kurama's head. Then Jon concentrate and transfer his Yang chakra. Kurama say Jon need to do this for some weeks until the Yang chakra make a core. After the core formed, Kurama can gather the Yang chakra himself.
Jon did that for the next 1 month, and now Kurama's Yang core has restored. He can gather Yang chakra himself. Jon also finally stabilize his colourless Armamant and he can harden it only for a moment. But the most progress is that he can use Armament without blocking his chakra like before.
Jon always try to use Armament when he open his chakra. He never succeed in the previous months, but a week ago, he finally succeed. Now he can use Armament while fighting normally.
Dragon also change his Armament training now. Jon need to fight with Revolutionaries that can use Armament. They only allowed to use Haki, and not jutsu or devil fruit. Jon like this new training more than the previous one.
6 months after Jon start his training in RA base, he can finally hardened his Haki. Altough he can only cover some parts of his body like hands or feet, but it's a big progress. When he understand how it works, it became easier to improve.
His Observation also improve greatly, and he has train chakra sensor. It's possible to combine it with Observation Haki, but he can't do it yet. He need more mastery over both techniques.
He also train some new ninjutsus in these months. He can train more but he want to have high mastery first before attempting more new jutsus. His old jutsus have become stronger too by now.
He also train his mangekyou, he can train it by meditating while it active and not really use it. Now he can store 20 m3 space, but his time stop hasn't improve. He also can use half humanoid Susanoo now. The humanoid Susanoo somehow looks like a golden Titan Eren with 4 hands. Just like what Jon felt after he can activate Susanoo, it have 2 ninjato swords.
Jon also try Susanoo's power like Yasaka Magatama and it's durability now. The humanoid Susanoo can take Dragon's attack that break his skeleton form, but it still cracked. Even so, Kurama said that Dragon didn't use his full power on that attack.
Except his progress in ninja arts and Haki, Jon also make progress in Rokushiki. He started training it about 2 months ago, and now he can use 3. Kami-e is easier because it is similar to Observation Haki. It helped him improving his Observation Haki too. But it's inferior, so he didn't really use it.
He also succeed training Soru and now try to combine it with body flicker. He will be able to move very fast if he succeed. He can't even imagine just how fast he will be if he use lightning mode too.
The last one he train is Tekkai, it help him defend like Armament, but it's different. Haki use spirit, while Tekkai use muscle and skin. But if he can combine it, his defense will be very high, even without armor. He just need to find a way that allow him to move while using Tekkai.
Today, Jon train again like usual, but he's alone. The others are busy with their works and didn't have time for training. Suddenly Dragon come with Koala to the training ground.
"You won't grow with training like this anymore, kid. So now you will go to missions and real battle. I will send you to some missions, so prepare yourself!"-Dragon
"YOSHA! Finally some real actions."-Jon
They go to Dragon's office and Dragon give Jon a paper filled with his mission detail. Jon is surprised, but he's also very excited.