Disclaimer: First Chapter
Story Start!

"That's amazing Naruto, you really do catch onto this kind of stuff quickly."

Naruto was standing in the middle of the Gravity Chamber, with a red aura around his body and his muscles trying to bulge in size, they were about 20% larger than they usually were. His hair was tinted orange thanks to the red aura around him.

Chakra
Ki
Spiritual Energy

The use of Ninjutsu was when you used your chakra to connect and manipulate Ki and Spiritual energy together, the energy of the body and soul, and change it in form or shape. Yang and Yin style jutsus were done when you used chakra to only manipulate one type of energy. Naruto, as an Uzumaki, had an extremely immense life force that gave him a wealth of all three energies to manipulate.

Naruto had been approached by a Trainer from another Universe who sensed his strong Ki.

"This technique was made for you, and you aren't taking any damage?"

"I am, I'm just healing faster than I take it." Naruto could feel the rips and tears in his body forming and healing... and since he was healing at a constant rate, his body was acclimating to the transformation he was using. "Kaio-ken... times 25..." Naruto increased the transformation even further.

He had never used only his Ki before, he always used Chakra to manipulate it, but he found a person who wanted to teach him a few techniques that he could use with Ki. Naruto had wanted to train with people from other universes.

Name: Son Goku - Sex: Male (Species: Saiyan)
Rank: Training Instructor
Libido Level: 25

"This technique is something I can't really use much anymore without hurting myself, but I guess I don't have your healing power." Goku was smiling as he watched it happen with his own eyes. He watched as Naruto's body very quickly adjusted to the transformation and increased power of the technique. His body healed visibly from the damage the technique caused, which allowed Naruto to visibly adjust to it as if it were his natural state.

It happened in 30 seconds this time.

He watched as the strain of using Kaio-ken x 25 on Naruto's body was reduced as his body healed stronger from the damage. The first time Goku used Kaio-ken times 4 he ended up damaging his body so much he couldn't even fight anymore... but unlike Naruto, he didn't have a super increased healing ability.

"Kaio-ken... times 40." Naruto jumped the power to an even higher level, and started to sweat under the huge jump in power. Bruises started to appear on his skin from the rips and tears in his body. His muscles bulged another 3% from the straight, but steam started to float off of his skin as he still healed.

Goku was encouraging him.

"That's it, keep it up. The longer you can hold out from the pain, the quicker your body will adjust. Hold out for another 2 minutes and your body will adjust to this transformation too." Goku was clapping his hands together with a whistle.

Naruto called himself a Failure and a Hard Worker, but that wasn't what Goku was watching happen in front of his eyes. Naruto was a hard worker, but the boy was also a downright genius when it came to talent. All he needed was somebody who could teach him correctly, and he flourished faster than anyone else could imagine.

"Kaio-ken... times 55." Naruto pushed the limits further.

'Muscles heal back stronger, and with his super healing power he isn't just adjusting to the Kaio-ken, he's making his base form stronger as well... his potential is insane.' Goku was smiling wider and wider as Naruto made use of a technique that even he couldn't use without damaging his body. Naruto adjusted even faster the more stress he put his body under, and the more he adjusted the faster he healed.

Naruto's muscles shrank back down now that the stress on his body was reduced, though his muscles were still 10% larger than they usually were. It was a small change, but it showed that his body was still adjusting in a way.

"Kaio-ken x 70."

Naruto's muscles bulged out again from the great strain, and the great pain of the transformation caused Naruto to twitch and writhe in agony. He didn't surrender to the pain though, instead he summoned forth the smallest amount of the Kyuubi's chakra from within him possible to increase the speed he healed at. Each muscle fiber on his body seemed to be twitching, but after a few minutes of constantly damaging and healing his muscles back stronger than before, Naruto's body adjusted even to this level of power.

"Think you can handle it further?" Goku asked Naruto.

Naruto grinned.

"Kaio-ken x 90." Naruto responded with the challenge of pushing himself to even further.

"Alright then, lets see if you can handle the height of the technique... the Kaio-ken x 100... the limit of what this-"

"Kaio-ken x 100!" Naruto pushed it to the limit, and Goku couldn't help the giddy smile and jump from foot to foot he did. He watched with baited breath for Naruto to adjust again, and though it took longer than before... it happened.

Naruto's swollen muscles shrank back down to just slightly larger than their normal size... a side effect of all the rips and tears they had gone through making his body ever so slightly larger than before. Naruto kept the technique active, and his body adjusted even more to the technique the longer he kept it active. The damage being done to his body was soon reduced to almost nothing at all, with the damage that was being done getting healed just as quickly as it was created... and then even that stopped.

After his body healed, repaired, and strengthened itself from healing hundreds to even thousands of times in such a short span of time, Naruto had adjusted to the technique to such a level that even the limit of the Kaio-ken no longer damaged his body.

A superhuman that could multiply all of his attributes by 100 times his base form.

The red aura around Naruto shrank down to just a mere inch above his skin, and the red tint on his body became glossier.

"Well..."

"... I've completely adjusted to it." Naruto stated as he moved around. He accidentally moved too fast and crashed into the wall, since suddenly being 100 times faster than he usually was, was an immense jump in speed that he wasn't used to. "... gonna have to get used to that though." Naruto stood back up.

"The Gravity in this room is set so that each of those bands around your arms and legs should weigh about 10 tons... how heavy do they feel now?" Goku asked, since 10 tons per limb was about the limit of his own base form. If he went Super Saiyan he could ignore such a limit and go 50 times stronger than that.

Naruto took the weights off and tossed them to the floor.

"I don't even feel them anymore." Naruto couldn't even feel the weight of the weights now that his body had adjusted. "Though... to be fair, my friend Rock Lee could handle weights that heavy without any techniques or transformations at all. He's been able to handle more than 10 tons on his legs since he was a kid." Naruto remembered when Rock Lee dropped his weights and shook an entire building with them.

It took him years of training to catch up to Lee without his weights on, and Lee was still faster when he came back from his training with Jiraiya, but he had closed a good gap of the distance. For a Shinobi, being able to lift a good several tons even without using chakra wasn't all that special. Wearing them constantly would wear down stamina though, so there was no point to it.

Naruto didn't use them because he had too much stamina, that the weights weren't effective against him.

Goku transformed with his hair going gold and eyes green.

"Well then, lets spar so you can adjust to those new speeds. This will be a fun spar... of course, no techniques other than our transformations. We don't want to break this awesome training room. Just fists." Goku raised his hands up.

-8 Hours Later-

"Okay... okay... that... that was intense." Goku was sweating.

"Want to keep going?" Naruto asked Goku as the sweating man was on his knees. They had been sparring nonstop for 8 hours, and Goku had started to run out of stamina during the halfway point. Naruto recovered his stamina quickly though.

Goku nodded his head and stood up.

-8 More Hours Later-

"Okay... I'm... I'm tapped." Goku was laying on his back in total exhaustion.

"Are you sure, I still haven't completely adjusted to the speed of this technique yet... think you can go a little longer?" Naruto politely begged Goku with both of his hands together. Goku turned his head to look at Naruto. Goku was smiling and laughing through pants of exhaustion.

Did this boy not have a stamina limit?

How long was he able to fight.

Goku pulled out a Senzu bean from the small bag at his waist, he usually gave them to Champions he was training to heal them and recover their stamina. Most people just couldn't keep up with him when it came to training, so he had never used them on himself before. He popped one in his mouth and crunched it.

He jumped up as all his stamina recovered, and he transformed again.

"Okay~! That sounds fun!"

-24 Hours Later-

"Okay... and I'm back up... I'm back up." Goku ate another Senzu bean and recovered his stamina again.

Naruto was exhausted, but he still seemed fine, as if he had stamina to spare still. It was actually starting to get a little unbelievable for Goku, since this was the Hour 40 of nonstop sparring with each other.

"Lets go, I think I've got your fighting style down now."

'His growth rate is insane... and his stamina seems bottomless. We've almost been training for 2 days straight, and he hasn't used a Senzu bean to restore his stamina... he's sweating and exhausted, but his stamina just doesn't end.' Goku was happier than he had ever been. He had accepted the job as a Trainer so that he could see the talented people from across the Multi-verse, but he didn't find a lot of people who had this level of raw potential.

Naruto's natural gifts were amazing.

'Not to mention, his body has Chakra and Ki... and Spiritual Energy or whatever that is. He has a wide variety of techniques he is capable of learning... and he's a natural talent. He picks up things fast. He's already talented at martial arts too...' Goku had watched as Naruto started to pick up and use the techniques that he used during the spar, and add them to his own fighting style. "... are you secretely some kind of Saiyan?"

"No?" Naruto was confused.

-28 Hours Later-

"Okay... I'm done... I'm tapped... I'm out..." Naruto collapsed with Goku that time as he ran out of stamina for real.

"Oh thank you..." Goku had never been happier to be done with a long training session before. The Senzu beans replaced the need for meals, and it kept restoring his stamina, but he was starting to run out of them.

Naruto was a stamina freak.

He had not used a single Senzu bean to restore his stamina during their entire sparring session, and he had not only mastered the Kaio-ken x 100, but he had even improved his martial arts to the next level from the constant sparring. He had taken nearly every single martial arts move that Goku used, and then adjusted it to fit his own fighting style, and started to make use of them. Naruto was a fighting genius and had the stamina and healing factor to keep going, and going, and going, and then going for more.

They had been sparring for 3 days straight.

"Here... this should help you get back home." Goku tossed Naruto a Senzu bean.

Naruto ate it and all of his exhaustion went away.

"Thanks! Wow, I feel fully refreshed... and it got rid of how much I needed to sleep too. I don't have a match until next week, so you mind if we go for a couple more rounds?" Naruto jumped to his feet, refreshed and ready for more training. "... oh... I've completely gotten used to the gravity here... want to increase it by a lot more and start again?" Naruto asked as he noticed he didn't feel the enhanced gravity at all, even in his base form.

Goku was sweating and smiling.

"Uh..." Goku just realized that he completely restored Naruto's stamina and energy levels back to normal with that bean.

The same Naruto who could fight for 3 days straight without food or rest.

"How about instead of sparring, I teach you... the Fusion Dance..."

"Oooh... sounds interesting." Naruto stated as Goku ate his last Senzu bean and restored his stamina. Goku slowly got back up.

"Well, it is when 2 people do a dance and fuse together. The fusion is way more powerful than the 2 people who fused combined... like... 1 + 1 isn't 2... but instead like 7." Goku used super basic math to explain it. "... you just control your energy to be about the same level as the person you want to fuse with... and do this dance... Fu... Sion... HA!" Goku did perhaps one of the goofiest dances of all time.

Naruto just watched and looked around.

"... I have nobody to fuse with though." Naruto deadpanned.

He blinked.

Naruto raised his hands up and created a single clone next to him, and he nodded to the clone. Naruto nodded to his own clone again, and they got a decent distance from each other. He and his clone had the exact same power, meaning that he didn't even need to try and match power with his clone.

"Oh! That's interesting. You CAN fuse with anyone or anything as long as the conditions are met, the rules of the dance don't say clones can't fuse." Goku watched as Naruto did a few practice runs of the dance with his clone, just to make sure that he got the dance down pat. The Fusion Dance was super easy to use, that a person could perfect it their first try if they really wanted to. Goku was curious about what would happen if Naruto attempted to fuse with his own clone.

What would happen.

"Fu~sion HA!"

There was a bright light.

Naruto... just Naruto was standing in front of him, only his clothing had changed to become Fusion clothing now. His looks remained exactly the same though, seeing as he fused with an exact copy of himself. His power sky-rocketed though thanks to the multiplication the dance gave his power.

"... Kaio-ken x 100."

'He fused with his own clone... so he's maximized the Fusion Dance thanks to just how in sync he and his own clone are... his potential is downright immense... but his growth rate is even more insane.' Goku nodded his head to himself.

Thankfully Fusions had a 30 minute time limit at most with this method.

-Later-

'Right... Ninjutsu is using chakra to manipulate Ki and Spirit energy... now I know how to use Ki and have some basic techniques... maybe I should find somebody who can teach me Spirit energy techniques too.' Naruto was showering off from his very long training session. His trainer for the couple of days had to call it quits, because he ran out of Senzu beans to restore his stamina with. Naruto was ripe with sweat though, so he needed to shower before he tried to find a teacher who could help him learn to make use of the Spirit energy side of his body.

Also, he and Goku had been hogging the gravity chamber for over 3 days straight, so at that point he was sure other people would like to use it too.

"Hey big guy, you mind moving out of the way... and not looking this way when I shower, I just got done training."

It was a tiny girl.

A girl shorter than he was when he was a 12, with a petite body and black hair... but the face of an adult woman with grey eyes.

"Long shot, but you wouldn't happen to know a Trainer here who can teach a guy how to use Spirit energy would you?" Naruto didn't look at the girl as she started to shower, since she asked him not to look at her. The showers were like the changing room, and not separated by gender, since the aliens (their species name was actually Enis) didn't understand that males and females of other species didn't normally bath together.

"You wish to learn to use... yes... actually, I do sense a great amount of spiritual power in you, far greater than a normal human."

The girl on the other hand didn't have a problem looking over at him as she observed the spirit energy of his body, and sensed how powerful it was without him trying to use it. She could also make out other forms of energy that he was using.

"Are you a trainer?"

"No, I'm a Champion, but I only do those stupid sex battles so that I can get access to these amazing training grounds, not to mention the fact I can get hundreds of years of training without any time passing in my home Universe."

"Oh... right." Naruto nodded in agreement without looking at her. She seemed excited about the training, and actually bored with the idea of sex fighting.

"In my world, you can share Spirit Energy with others... I sense you have another form of energy. If you are able to share that power... then I would be willing to teach you what I know about Spirit energy, if you transfer some of that... other energy..."

She was in it for power after all.

"If I share my chakra, you'll teach me how to use Spirit energy... sounds like a deal... uuuuuh."

"Call me Rukia." Rukia introduced herself rather casually. She wasn't looking at Naruto anymore, she was washing her hair. If she could get access to another form of energy to enhance herself, then that would make teaching somebody else very much worth the effort. "So... can you share chakra with others?"

"I don't know... I'll look into that." Naruto wasn't sure if he could do that actually.

Rukia sighed.

"Well... tell you what, if you can teach me any martial arts you know, I'll consider that a good enough trade for Spiritual energy lessons." Rukia was fine was less, if she could at least learn a martial art from another universe. Anything she could do to enhance her own abilities would be greatly appreciated after all.

Naruto nodded his head.

"Now THAT I know I can do."

Awesome, what good luck that he ran into somebody that could reach him how to use the spiritual side of his powers.

Chapter End!
Please Leave Me Lots of Nice Long Reviews, But No Flames Please!

Notes: Remember, the Ninja Humans from Naruto DO use chakra to control their Ki and Spirit energy, so they DO have 3 forms of energy in their bodies.
Yin Release is when a Ninja uses their Chakra + Spirit Energy
Yang Release is when a Ninja uses their Chakra + Ki
Ninjutsu is when a Ninja uses Chakra to fuse Ki and Spirit Energy
Senjutsu is Nature Energy + Ki + Spirit Energy
Naruto DOES have the ability to use Ki and Spirit energy without using Chakra, since he showed he can use Senjutsu. This means that all Naruto needs is a teacher who uses Ki, and a teacher who uses Spirit energy, to learn techniques from other universes. Naruto-verse Humans are unique in that they have 3 different forms of energy inside their bodies.

Fun Fact: Rukia is 144cm tall, which makes her shorter than Naruto at the start of Naruto, who was 145.3 cm tall.