(mid-October, year 51 AK)
...
Yuta sat cross-legged on the ground at the training grounds, closed his eyes and followed the feeling that the River of Time was giving him through his connection with it. If before he only had a vague sense of it, and only when he fully concentrated to sense it too, now it felt strong and steady, and it only took a small amount of effort to follow it through to its source.
With just a small effort, Yuta instantly appeared inside his mindscape. He looked around once again, nothing has changed since his last visit here, the water surface went in all four directions all the way into horizon, splitting the entire world into two halves, he once again felt small and insignificant in the presence of the grand and mysterious River of Time.
He was sitting cross-legged on the smooth surface of water, although the surface was calm and smooth with no ripples, Yuta could feel a strong and steady current underneath the surface, not by physical contact but he rather instinctually felt it.
'That was unexpectedly easy.' Yuta thought, his mind became unnaturally calm, 'I no longer have to assume a comfortable position and spend time and effort concentrating to get here, I can do it anytime instantly now.'
'I feel so calm and comfortable, all the problems and worries, all the negative emotions are washed away while I'm here. I feel so at peace now that I could sit here forever... '
...
'Sigh, I must focus on my goal here, I can't just waste all my time and energy by doing nothing, no matter how nice that would be.'
Yuta focused his attention on the River of Time, he tried once again the same thing he did the last time, he followed his connection with the River of Time with his consciousness and tried to get the understanding of it, of how it works and how he could use it.
He once again felt that this is working and he about to figure something out, but this time he didn't felt extremely tired as he wasn't exhausted like the last time when he spend all his mental strength to forge his way in here and connect with the River of Time, now he felt even more energetic instead, since the River of Time strengthened his soul.
Next instant Yuta felt that he started to submerge quickly into the water. It's a good thing that his mind was in an unnaturally calm state, if not for that - he would've panicked, and who knows what would've happened if he was to lose concentration and falter during this crucial moment.
As Yuta remained calm, he concentrated on the goal before him and wasn't distracted by the sudden submerging into the river. As soon as he submerged underwater completely, Yuta felt that the soothing-cold feeling intensified, and no longer just his emotions being washed away, but now his thoughts and senses too started to fade, overtaken by the sense of peace, calmness and silence.
In the state, where there are no thoughts, no feelings and no senses of any kind, deep in the dark waters of the River of Time, Yuta's small five-years-old body was floating without any movement, his cross-legged pose is no longer present, his arms and legs are floating in the water freely, his short black hair was stood up and swayed by the current, his eyes are closed.
Although Yuta's body was being constantly washed over by the steady current of the river, it still stayed in the same place he was submerged and wasn't moved by the current in the direction the current was flowing.
Yuta's mind was empty, devoid of any urges and desires, he was also lost all sense of time, he doesn't know if a few seconds passed since he submerged into the River of Time, or maybe hundreds of years... He was truly and completely at peace...
After an unknown amount of time passed, if the concept of time was even applicable in this place, Yuta felt an unpleasant feeling and instinctively tried to resist it, but no matter how hard Yuta resisted, he seemed powerless against that unknown force.
After a few moments of futile struggle, Yuta slowly surfaced and was pushed above the water surface, the water surface became solid for him once again. He opened his eyes and started coughing, water poured out of his mouth, and he finally drew a ragged deep breath with some effort, water was dripping from his whole body.
His consciousness returned to him and as soon as he was able to think again, he felt exhausted and was forcefully thrown out from his mindscape.
Yuta opened his eyes in the training grounds and drew a deep breath, he started panting, his eyes wide open with a strong sense of fear in them.
'What... What the hell was that!?' Yuta thought panicky, 'Am I almost died in there?!'
Yuta hastily looked around instinctively, as his flight or fight instinct were still kicking in, along with a ton of adrenaline.
'I'm safe now, I must calm down...' He managed to take hold of himself with some effort.
...
After a minute Yuta managed to calm down and start to analyze the situation he was in.
'What happened back there?' He thought, 'When I wanted to get an understanding of the River of Time, I suddenly start to submerge inside it, but that almost killed me...'
'My consciousness faded and all I instinctively wanted is to stay there forever... But then I was dragged out of the River of Time by some force... I feel like that force was not originated from the River of Time itself, it was probably the effect of my Time Control ability that saved me and didn't let me to completely dissolve in the waters of the River of Time...'
...
'The understanding of the River of Time... Understanding...'
As Yuta thought about his attempt to understand the River of Time's inner workings, he suddenly found some knowledge about it in his mind he was sure he didn't have before. As he went over this new knowledge and sorted it out, he gained a better understanding of what happened to him.
According to this new knowledge, The River of Time inside his mindscape is just a visual and mental representation of the concept of time itself, there is actually no such thing as the River of Time, or its waters, it's just a metaphorical image created in his mindscape so Yuta could comprehend the concept of time to some extent and interact with it through its metaphorical representation, nothing more.
And although the River of Time doesn't exist on its own, it is still a real thing, as it is the metaphorical representation of the concept of time, and it allows Yuta to comprehend and interact with the concept of time through it.
Normally, nothing like that would've being possible for anyone in this world, not even Hagoromo himself or even for the Otsutsuki clan. They sure can utilize some of the powers of the time domain, like time-travel with the help of some special artifacts and such, but never to get into direct contact with the time concept itself, not to mention to influence it directly.
But not for Yuta, as his Time Control ability grants him the connection to the time concept itself, and the authority over it, so he is able to interact with it directly through its metaphorical representation in his mindscape – the River of Time.
As to what extent Yuta would be able to use the powers of the time domain, it would fully depend on him, on his understanding of the time concept and its laws, as well as on his own imagination and ability to find the most effective and creative ways to bend those laws according to his will.
But even with his newfound authority over the time domain's power, and ability to ultimately bend the time to his will - to actually do so he must be strong enough himself.
In other words, if the time concept, or rather its representation – the River of Time is like a car, a sport car that is the best on the market at that, and the Time Control ability is like a key to the car, then to actually drive the car Yuta has to learn how to drive on his own, and also he has to produce the fuel for the car himself.
In this analogy Yuta already acquired the understanding of how the gas pedal and steering wheel of the said car works and such, he only lacks the actual driving skills, in this aspect he only needs to proceed carefully and figure out to what extent he would actually able to wield the powers of the time domain.
As for the fuel for the car from the analogy, it's his spiritual energy, how abundant and potent it is – will directly influence how fast and how long his metaphorical car would be able to go. In other words, his spiritual energy is the only limit of how much power of the time domain Yuta would be able to command.
'Spiritual energy huh...' Yuta thought, 'So physical energy from the body training is useless for the Time Control ability. This is why only my soul and spiritual energy was strengthened by the connection with the River of Time, but not my body and physical energy?'
'Spiritual energy originates from the soul and mind, I think, but I don't know much about it besides that. The only thing I remember from the anime, it was mentioned during Naruto's sage mode training, and it's being the source of the Yin release and genjutsu, or maybe genjutsu is the Yin release...'
'There is a lot of things I must confirm when I get into the academy, maybe I can ask Manabu about such things, but knowing him he would probably say something along the lines "don't rush into complicated stuff and focus on the basics..."'
'My spiritual energy was strengthened by the River of Time, today I even dived inside it, maybe I could use this as the way to improve it!' Yuta thought excitedly, but when he focused on his chakra and compared the feeling it gave him now, he sensed no difference in its coldness or heaviness compared to the last time.
'Well, no easy ways to cheat for me I guess, I have to improve my spiritual energy the normal way, as all shinobi do in this world... How do they even improve spiritual energy though? Ninjutsu and genjutsu training, maybe, studying? I must find out, it is essential for me after all.'
'As for to what extent I could use Time Control with my current amount of spiritual energy, I don't think that would be much.'
'I'll try to come up with a list of time powers I could try to use, like time-stop, time-acceleration or time-travel and such, and then try them one by one with my current spiritual energy and my current understanding of the time domain rules that I've got today from submerging into the River of Time, and see what happens...'
'But I'm too exhausted today, I'll start experimenting with that tomorrow.'
--- AN ---
Emm, guys... I didn't mean it, I promise. I was about to get into that damn Time Control ability and what it can do in practice... but it didn't come up, and the chapter ended up on the cliffhanger again. You all probably hate me at this point, understandable though...
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