And that concept is 'Extreme'

  Lorien wanted to see if by taking this concept as a base, could his ability enable the 'Power exertion' part to push anything he does to the extreme, be it defense, attack, or speed...

  This could also be applied to the control part, swordsmanship, and martial arts he previously mastered

  By doing this it'll allow him to use his power to the absolute limit, not wasting any of it, and even bursting with more than 100% of the power

  So with this in mind, Lorien's ability resumed its work, quickly transforming the 'Exertion' Part of the breathing technique

  Problems in the breathing pattern were quickly found and corrected, and then it was quickly complemented with new breathing patterns and then perfected

  Following that, and with the concept of 'Extreme' as the base, subtle changes were made everywhere, as some weird but mysterious 'Aura' was added to it

  Those changes continued for a while before it finally ended having finally perfected this part

  But it didn't end there as it quickly started transforming the previously finished 'Control' part, also adding the same concept of 'Extreme' to it

  With this transformation proceeding, fine changes started occurring similar to the 'Exertion' Part

  This lasted for another couple of minutes until it finally concluded

  And with that, Lorien was left with was a complete breathing technique that reached the absolute limit in both power control and exertion

  And thanks to the concept of 'Extreme' as a basis it had no shortcomings other than requiring a lot of physical strength from its user and causing a huge physical burden on the body

  But thankfully all of this wasnt a problem for Lorien considering his physical strength

  After having got the breathing technique Lorien then proceeded to check his Energy reserves to see if it was possible to continue right now

  But sadly after a quick check, it was apparent that it wasnt, as his Source Energy was nearly depleted

  This wasnt because of creating the breathing technique, as the sun breathing technique provided enough information causing the energy cost to significantly get reduced

  Most of the energy was actually spent on deducting the concept of 'Extreme' and merging it into the technique

  Frankly, Lorien didn't expect it to be completed at once, he was prepared to do this multiple times

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  But it seems that with the increase in his personal strength the energy cost for realizing things also goes down

  Looking at this New Technique that just appeared in his mind Lorien held back the urge to try it as his work wasnt done yet

  What he needs to do now is merge this breathing technique with his swordsmanship and martial arts while also adding this concept to them

  Then he needs to transform all of this into an 'instinct'

  But even with all of this planned and ready for execution, Lorien isn't able to do it right now as he needs some time to recover some Energy

  So he decided to sleep off the waiting time as it won't take that long anyway with his recovery speed

  Moreover, he's been tired from all the travel he did, so a good nap right now would be greatly appreciated

  Standing up from under the tree he walked towards the house and then towards his bedroom

  *Yaaawn*

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  Hours later

  Lorien woke up feeling refreshed, all the mental fatigue he previously had was swept away

  Stretching lazily, a small grown exited his mouth

  'Ahhh～ Nothing better than sleep'

  After fully enjoying the first couple of moments after waking up, Lorien checked his Source Energy reserves, and as expected it was indeed fully restored

  Seeing this he didn't even bother to change position as he laid back on the bed and started using his power

  [Dream/Reality]: Merge and Perfect

  And then with it working its magic, all of the information in his mind about Martial arts, swordsmanship, and the 'Extreme Breathing Technique' started merging with the concept of 'Extreme' as the core

  With them merging, some moves, breathing patterns...etc were discarded while others were quickly added

  This lasted a full 20 minutes until it finally stopped, all the separate information disappeared, leaving only one seamless bulk of information

  This information contained martial arts, swordsmanship, power control, and energy exertion

  And what they all had in common was this newly added 'Extreme' Concept

  This helped push the previously perfect swordsmanship and martial arts to a whole new level officially reaching the [Extraordinary] Level in the 'martial path'

  But this wasnt the end as there was one last step before Lorien finishes his 'job', and that is to turn everything he just got into instinct

  So, after making sure that his Energy Reserves should be enough he started without further ado

  [Dream/Reality]: Turn into Instincts

  With his ability resuming its work, this new 'knowledge' started getting engraved into his being slowly transforming into instinct

  His normal somewhat chaotic breathing pattern was rapidly changing into that of the Extreme Breathing Technique's

  New information and muscle memories about physical power control and exertion started appearing and got engraved into his being, enabling him to master it as if he had practiced it himself for decades

  The previously engraved knowledge and Instinct about Swordsmanship and Martial arts were rapidly getting modified and updated

  The previous moves were subtly changed and improved while also adding some other things to it which was [Mystery]

  This lasted for half an hour before it finally ended with this new knowledge having got fully engraved into him turning into Instinct

  And as soon as it did Lorien opened his previously closed eyes

  Doing so Lorien quickly noticed something strange

  His perception actually changed, everything around felt like it was in slow motion

  Everything seemed clear like never before, it felt like bullet time

  But this only lasted for a moment before this state receded as Lorien stopped using it

  It only took him an instant to figure out what it was as all the information was in his brain, and engraved into his instincts so he could use it intuitively without an issue

  That was the 'Transparent World', also known as the 'Supreme Territory' in the Demon Slayer World

  Following this Lorien stood up and took out his Sword as he walked out moving in the direction of the backyard intending to fully inspect the new gains

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