In the Kimetsu no Yaiba verse, all Demon Slayers are gifted with their own personal Nichirin Blade once they pass the final Selection exam. These blades are critical to Demon Slayers since it's their primary weapon in combat. The Demon Slayer Corps is an organization of warriors tasked with protecting Japan and eliminating the demon threat once and for all.
Demons are powerful beings with overwhelming strength and the ability to regenerate, with the sun being their only weakness. As a result, a unique ore that constantly absorbs sunlight is used to forge Nichirin Blades, making them invaluable to demon slayers. Nichirin Blades often take on a different color depending on their owner, making every blade unique.
The Kitmetsu No Yaiba-verse consists of many such demon slayers, each with a different color providing special abilities to the blade. So far in the Kimetsu no Yaiba-verse, fans have seen several such blades like Giyu Tomioka's blue Nichirin Blade, Kyojuro Rengoku's red blade, and Zenitsu Agatsuma's yellow Nichirin Blade.
As mentioned above, each color adds some elemental properties to its blade; for example, yellow is for lightning, red is for fire, and blue is for water. However, our protagonist Tanjiro Kamado has a black Nichirin Blade, and fans have some theories on why that is the case.
When Tanjiro first received his Nichirin Blade, nobody in the Kimetsu no Yaiba-verse expected his blade to be black. The swordsmith Hotaru, who creates these special blades, and Tanjiro's teacher, Urokodaki, believed that Tanjiro's sword would turn red because of his hair and eye color. They also mentioned to Tanjiro that the color would bring him good luck.
However, fans who were watching the series at the time expected his blade to turn blue. This was because Tanjiro, like Giyu, uses the Water Breathing Style. However, when Tanjiro wielded his sword for the first time, it turned black, catching everyone by surprise! Like Tanjiro, we don't know much about why his blade is black.
Of course, it has been foretold that a Black Nichirin blade will bring bad fortune to its wielder in the series. It is also said that the owner of the black blade will die young. Apart from this, not much is known about the properties or symbolism of the black Nichirin Blade.
If you've watched Demon Slayer: Mugen Train, then you might agree with this theory, which is canon since it comes from the character Kyojuro Rengoku. In the Mugen Train film, Rengoku talks about the five basic types of Breathing Styles known in the Demon Slayer's history, namely Water, Flame, Thunder, Wind, and Stone. He then mentions that a black Nichirin Blade signifies a user who can't find one breathing style to stick to.Â
This theory makes sense, considering Tanjiro uses both Water Breathing and Hinokami Kagura, a flame dance that utilizes the forgotten art of Sun Breathing. In the first episode of the Demon Slayer: Entertainment District Arc, Rengoku's father tells Tanjiro that Sun Breathing is the original Breathing Style, revealing that all other styles derived from it, making it the strongest one of them all.
The Demon Slayer series has also often mentioned how the color black absorbs all colors and is considered a combination of them. This has led to fans speculating that Tanjiro's black Nichirin Blade symbolizes his potential ability in mastering all of the Breathing Styles.
Whether these theories are accurate or not remains to be seen; however, we're sure fans will find out more about the abilities and significance of Tanjiro's blade. For now, fans can check out the latest episodes of Demon Slater: Entertainment District Arc on Funimation or Crunchyroll. Indian fans can check out the latest episodes on Netflix.
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