On the chakra reading part, I agree that I don't think it's been directly addressed before. Winging it sounds like a good idea
However, when I read your post, I immediately thought of Jiraiya checking out Naruto's seal before the Chuunin Third Exam. That was specifically just to see his seal and to undo Orochimaru's counteracting one, but I always thought that the main chakra coils were situated around the stomach/navel anyway. So if you fudged it a little, it would sort of make sense for Itachi to put his hand against Naruto's stomach or something and hopefully it won't look too whimsical, haha.
Here are some pics of Jiraiya and Naruto, and the chakra pathways
From chapter 91:
About Tsunade, I for some reason always naturally assumed it was genjutsu or transformation jutsu but it's a curious subject now that you bring it up! I searched on Narutopedia (always a good place for info) and this is what it says under the 'appearance' section:
Like wikipedia, the info isn't always correct. If we assume that this fact is right (even if it's not, I guess fanfiction has its perks), then Tsunade's disguise is nothing more than a complex transformation jutsu, which is usually performed using handseals.
Hope that helps and good luck with your writing!
Thanks - and those manga pics are great. I remember Jiraiya checking out the seal and then removing Orochimaru's handiwork. But I'd forgotten about the little flames at Jiraiya's fingers.
Kakashi makes mention of how vast Naruto's chakra reserves are (about four times as mich as his, and it could be 100 times if he didn't have to hold back the kyuubi) but it never comes right out and says how Kakashi knows it. Did Naruto have a physical? Or did Kakashi himself read his chakra levels?
So I need Itachi to read Naruto's levels, just like Kakashi did. (In my ff, Itachi is functionally taking the place of Kakashi as a sensei of sorts.) And I feel like reading chakra levels is one of those technics that might overlap a medic's skills. Medics would be trained to do it, but some adept shinobi might know how to as well. Sound believable?
And since it's just chakra levels, not the full kyuubi seal, I'm guessing you could read it anywhere...so I've written Itachi as having grasped Naruto's wrist and read his chakra levels through his arm. Seems like the most convenient spot. Easy to write about too! But I did include a sense of feeling based on the image of warm chakra flames atop Jiraiya's fingers. So it would feel a little warm to Naruto.
Thanks too for the insight about Tsunade. I agree that it's probably a complex transformation jutsu. But since it's complex, and Itachi's performing it for the first time, I'm having him draw out a seal on the floor, then plopping Naruto in the middle to perform the jutsu. I know it's kind of bending the rules — can you use a seal in conjunction with a hand-sign jutsu? — but it makes a much better scene. You get the feeling that Itachi's not completely confident with what he's doing, and that it's an important jutsu that Naruto's about to undergo, and he doesn't want to screw it up.
I'm not so terribly concerned about being accurate as much as I don't want to get something ridiculously wrong. Above all, I want the storyline to move ahead believeably.
@Toasty and Konoha, you're right about Naruto sensing other chakras as he matures. So it would make sense that a powerful shinobi would be able to sense chakra as part of his vast skill set. And knowing that, it makes it much easier to believe that Itachi would have mastered some low-level medic skills to help him analyze his friend or opponent. Or pet jinchurikki!
Thanks guys!
This is what I came up with for the Itachi/Naruto/chakra level/transformation jutsu conundrum!
"So Naruto Uzumaki, your shinobi training starts now. After last night, Konoha is probably already in pursuit…tracking both of us." A strange emotion flickered across Itachi's face, but was quickly gone. "We need to keep moving. But your looks are rather…distinctive."
Embarrassed, Naruto rubbed a hand over the back of his neck.
"You'll need a disguise."
"Really? Like different clothes or—"
"No, something permanent" Itachi frowned at his cheeks. "Especially for those lines."
Naruto beamed with excitement.
"The extent of what I can do depends on your chakra levels, but I'm hoping that since the Kyuubi's chakra is infused with your own, it will be high enough to sustain a transformation jutsu…."
Itachi took Naruto's hand, wrapping his long fingers around the boy's small wrist. There was a warm tugging sensation beneath his grasp.
Naruto watched his hand, the feeling getting stronger. "What are you—"
"Are you always this warm?"
"Um…yeah?"
Itachi frowned, then moved his fingers, grasping a little higher up on his forearm. Then he frowned again.
"Let me see your other arm." He tried a few different places, but the result was the same.
Naruto was becoming concerned when Itachi suddenly released him with a great exhale of breath. "Well that makes everything easier."
"W-What does?"
Big blue eyes followed him across the room where he retrieved a scroll from his bag. Itachi clutched it tightly until the middle glowed and a seal appeared. Satisfied, he strode back to the center of the room.
"Your transformation justu. You have an astonishing reserve of chakra. More than anyone I've ever known…." He shook his head at the discovery.
Flicking back the seal, Itachi unfurled the scroll between them and squatted down to study it, brows furrowed. Naruto scanned the document as well, eyes traveling up and down the rows excitedly. It was jam packed with writing and symbols, but more interesting, it was an official shinobi scroll. He could get enough of it.
He was just leaning out, tipping his head upside down, when Itachi's voice broke the silence.
"If you have to go to the bathroom, do it now," he said, never looking up. Naruto shook his head anyway. "This is going to take a while," he said, more to himself than the boy. "But when you wake up, you should be perfectly disguised."
Itachi scrawled out some lines on the floor, plopped Naruto in the middle, and began a complex set of hand signs. Naruto was so excited. He was determined to stay awake and see the magical transformation occur…but he passed clean out after the second set of hand-signs.
Itachi snorted and left him sprawled in the center of the web to finish applying the jutsu. It was an exhausting one. The boy would certainly be asleep for hours. And when he woke, he was sure to be starving. They'd have to move out immediately. He hoped nothing went wrong.
Sure enough, hours later the boy sat up with a clutching his stomach and head. But even from across the room, Itachi could see that the jutsu worked.
"Soooo hungryyy…." Naruto said groggily. He rubbed the ache at his temple, distantly aware that his hair felt more coarse than usual. Why was he sleeping in the middle of the floor?
Standing up took a near monumental effort: Muscles he didn't even know he had ached and burned. But fully righted, feet planted firmly against the floor, he felt the aches just melt away under a soothing, almost numbing warmth. He tightened his fists, testing out the muscles in his forearms. No, they felt alright. The pain was gone. Strange….
Itachi watched Naruto's slow progress but did not move. He was curious to see if the kyuubi would heal its vessel. That jutsu would put most grown men down for a week. Maybe more. But there was Naruto, getting up on his own from the middle of a blackened jutsu circle, stretching as if he'd just finished a moderate training. It truly was a sight to behold.
Itachi hooded his eyes. It was breathtaking to think of how much power was contained in that single boy….
Naruto's stomach growled loudly. He clamped a hand over his gut and looked around, eyes finally alighting on Itachi.
"I'm starving," he grimaced. "Is there anything left to eat?"
"No," Itachi said, getting up slowly. Even administering the jutsu took a toll, but he'd be feeling better soon enough. "Come on, let's go outside."
Naruto shrugged and followed Itachi through the hazy blue light at the entrance. Stepping out into the sunshine, Naruto was so glad of the sun on his skin, the fresh air. He felt good, energized. He was free. He lifted a hand to shield the light, and found Itachi scanning his face intently.
"It's good…great, actually. You look completely like a completely different kid. Now all you need is a new name."
Naruto patted his face, then pulled down a lock of his hair, realization dawning now as to why it felt so strange. Yep, it was thicker, coarser and…and…brown?
"The lines are completely gone, too."
"Really!?"
"See for yourself." Itachi pointed to a thin spring trickling weakly beside the rocky outcrop. Naruto bounded to it knelt down, bobbing his head over the the little puddles, excitedly trying to see all of his face at once. Brown freckles that dusted his nose and cheeks. It was as if the marks from his cheeks had just been shifted and scattered. He wiped at the new freckles but they wouldn't come off.
His yellow hair and blue eyes were gone, replace by brown. But he didn't care. He stared at the reflection as if he'd never seen himself. A slow smile crept up his face.
He looked like an average kid. He looked like anyone else. He was free.
Naruto turned back, ready to burst with joy. But Itachi was already moving on to the next task. He hitched up the rucksack at his shoulder.
"We need to move. And we need to get supplies." Naruto nodded.