Breathing styles are the main power system within Demon Slayer, and have been cultivated over hundreds of years. There exist some characters though, with unique enough fighting styles that they were able to invent brand new breathing styles.
In the harsh world of Demon Slayer, the gap in strength between demons and humans is only made manageable due to the use of breathing styles. By precisely controlling their breath and movements, demon slayers are able to enhance traditional swordsmanship and reach a level of power that can contend with the supernatural demons. Most characters use long-established and reliable breathing styles, but for some, the old styles were not appropriate for them, so they had to develop their own forms of swordsmanship.
Demon Slayer: Every Unique Nichirin Blade Introduced So Far
Having been raised in the forest by wild boars, Inosuke never learnt how to even read, let alone wield a sword. What he did learn though, was how to fight like a wild animal. So, when he ended up defeating a demon slayer who was passing through his forest, Inosuke took interest in the art of swordsmanship, but bent it to his own animalistic preferences.
Thus, beast breathing was born. Inosuke not only customized his nichirin blades by denting them to be more saw-like, he also chose to wield 2 swords as opposed to the usual 1. These modifications are meant to imitate the fangs of a wild animal, ripping and tearing with reckless abandon. The style also makes great use of Inosuke’s agility and strong senses, with several forms involving aerial attacks, and one entirely dedicated to locating enemies.
While she was originally trained in the flower breathing style, Shinobu eventually found that she couldn’t cut the heads off demons
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