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Warning: the following article contains spoilers from the Demon Slayer manga. Read ahead at your own discretion!
In the world of Demon Slayer, weapons and how to channel them is key in defeating the demons. With breathing styles and total concentration breathing one can optimize their skills.
However, the blade of the weapon is just as special! The nichirin blade is a testament that no breathing style is alike.
If you’ve got a keen eye for details, you must have noticed the colour of blades. With Giyu’s blue and Zenitsu’s lightening yellow, most of our main characters have blades that match their personality and breathing style.
So, read ahead if you’re interested in knowing everything about nichirin blades!
What is a Nichirin Blade in Demon Slayer?
Nichirin blades are special blades that kill demons. Their uniqueness comes from its colour changing ability and being the only weapon that can effectively kill a demon (wisteria is the only other thing that can kill a demon).
This is because of the ore used in the blade, which has sunlight absorbing qualities. Naturally, it is effective against demons who burn whenever exposed to sunlight.
Moreover, Nichirin Blade directly translates to “sun blade” in English, an ode to its aforementioned ability. Other than that, Haganezuka mentions that they are also called “color changing swords”.
However, a nichirin blade may not always be your usual sword! With the Hashiras, we see that many, such as Tengen and Mitsuri do not use an average katana.
The blades can be adjusted to different types of lengths and weapons according to the wish of the user.
The phrase “destroyer of demons” is inscribed on the nichirin blade of all hashiras.
How are Nichirin Blades made?
The first step to getting a nichirin blade is passing the Final Selection, the entrance examination to becoming a Demon Slayer. A forger from the Swordsmith Village is then given the responsibility of forging the weapon.
They then present it to its user. After passing the Final Selection, the new members of the corps get to choose their own ore.
Despite that, the blade’s composition is heavily made up of what Haganezuka calls the Scarlet Iron Sand and Scarlet Ore.
This is probably a mythological reference to Hihi’irokane. It was a magical ore that was used in ancient times. The Japanese Regalia are said to be made of this ore.
The name basically means “brilliant scarlet metal” due to the fact that the swords forged from it resemble the sheen of a flame. Additionally, they are conductors of emotions.
This is probably why these blades change colour in Demon Slayer!
Nichirin Blade Colors explained
The colour of the sword changes when its user first pulls it out of its sheath.
As mentioned above, its probable that the changing of the colour has to do with the ore being a conductor of emotion, so the blade takes the colour of something that means to the user.
This is where breathing styles come in! All blades signify colours that have qualities that resemble the characters!
Rengoku Kyojuro explains to Tanjiro about the five main breathing styles and their derivatives.
This colour coding is ingrained in the style’s symbolism; a fiery red for the flame breathing or a calming blue for water.
With this, let’s look at the breathing styles and accompanying nichirin blade colours!
Red Nichirin Blade
The colour red is associated with the Flame Hashira, Rengoku Kyojuro. Symbolizing self sacrifice and passion in Japanese culture, red suits the blazing strength and ideals of Kyojuro.
Red is a colour sacred to Japan and also represents fighting spirit and protection, which is something Rengoku abides by till his death.
His attacks are brutal and quick, synonymous to hot lava that swallows everything on its path.
This red is not to be confused with the “crimson red” nichirin blades (more on that later!)
Blue Nichirin Blade
Blue nichirin blades belong to those who practice water breathing. Opposite to the dazzling aura of red, blue smybolises calmness and passiveness; attributes we see in all water breathing users.
Despite their less flamboyant appearances, they manage to become one with water and save others in a pinch. Both Urokodaki Sakonji and Tomioka Giyu have blue coloured blades.
Yellow Nichirin Blade
Zenitsu’s nichirin blade is yellow, symbolising his breathing style: Breath of Thunder. Zenitsu’s blade has a lightning bolt across the length of his katana rather than a solid sheet of colour.
While its obvious yellow is meant to represent lightening, yellow in Japan denotes sunshine and flowers. Zenitsu is truly the sunshine boy of the trio!
In Japan, a person with a “yellow voice” is said to have a shrill voice. I am sure Zenitsu is the first Demon Slayer character that came to your mind!
Green Nichirin Blade
The Wind Hashira, Shinezugawa Sanemi’s nichirin blade is in green colour.
Much like in other cultures, green also resembles appreciation for flora. Despite that, green also represents youth and energy. This matches well with Sanemi’s behaviour, who’s quick on his feet.
Wind is also connected to the colour green, so it makes sense this colour is used symbolise this element.
Indigo
Hashibara Inosuke’s nichirin blade is in Indigo/grey.
Fun fact, indigo is a natural dye that has been used in Japan for centuries.
In this case, Indigo means so much more! Indigo represents sincerity. Inosuke has shown his unwavering loyalty and having the back of his comrades time and time again!
Pink
Kanroji Mitsuri’s nichirin whip is in the colour pink.
In Japan, pink represents good health and femininity. It also represents spring. If I were to describe Mitsuri, these three words hit the spot!
With Mitsuri embracing the way she is, she is an empowering woman indeed! Her hair is pink because of eating Sakura Mochi. You guessed it right- Sakura (cherry blossoms) are the symbol of spring!
Light Pink
The Flower Breathing style is shown with light pink. Tsuyuri Kanao and Kocho Kanae’s blades were in this colour. While pink can be used to signify the flower breathing users too, light pink smybolises tenderness.
PS- that doesn’t mean you can take them easily. Flower breathing is an insane technique!
Lavender
Serpent Hashira Obanai Iguro’s nichirin blade is in the colour lavender.
This flower represents faithfulness in Japan. Obanai embodies the adjective with his undying love and desire to make Mitsuri happy, even if he can only do it in the afterlife!
Also being symbols for calmness and silence, it suits Obanai’s covertness quite well! (or, it could just be his snakelike way of moving around)
Periwinkle Purple
Similarly, Insect Hashira Kocho Shinobu’s nichirin blade is in a periwinkle purple colour. Seeing her blade, it wavers between light blue and lavender, which is why periwinkle is the perfect choice!
The colour signifies serenity and everlasting love. This sits well with Shinobu’s story. Her serene eyes hide the anger of having her sister taken from her.
Her bright persona and joviality is a testament to her everlasting love for her sister as she tries to honour her in her daily life.
Periwinkle is also known as the “flower of death”.
White
The Mist Hashira, Tokito Muichiro’s nichirin blade is all white. Like red, white is also a colour that is precious to the Japanese.
The colour was worn during mourning until the onset of western ideas in Japan in the late nineteenth century. This has to do with Buddhist tradition.
Of course, it represents purity as well! The colour white often describes mist too. Muichiro, after losing his twin, is in mourning and is amnesiac, which misted over his personality.
Regardless, he is skilled and determined on his goal to eradicate demons. Since he’s the youngest hashira, white also resembles his position in the age hierarchy as another colour of youth.
Amber
The Sound Hashira, Tengen Uzui’s nichirin cleavers are in amber. Amber represents energy and boldness.
Tengen is bold, taking pride in his flamboyance, which makes sense why the colour denotes him. Sound “energy” is Tengen’s weapon to taking his opponents down, therefore the colour represents the hashira very well.
Grey
Stone Hashira Gyomei Himejima’s Nichirin spiked flail and axe are made of the same ore used in nichirin swords. The only difference is in the design of his weapon, which is grey in colour.
While one would usually correlate grey with dullness and ultimately loss of sight in Gyomei’s case, the colour represents more positive things in Japan.
Grey shows maturity and reliability, two attributes that make Gyomei not only approachable but the strongest Hashira of all.
Purple
Upper Moon 1 Kokushibo uses his own breathing style known as “Breath of the Moon”. The colour of his sword is purple. As with the rest of the world, purple symbolises nobility and royalty in Japan.
This mirrors Kokushibo’s grand appearance. Other than that, the colour can also signify arrogance, which is his hamartia.
Black Nichirin Blade
In the story, Tanjiro is the only known character that has wielded a black blade. Naturally, black is a colour correlated with evil. In this case, it represents mystery.
Why did Tanjiro’s blade turn so? While it makes sense it wasn’t blue, Haganezuka was expecting red. Does this have to do with his ability to practice two forms?
You can read more about this in our blog explaining the reason why Tanjiro has a black blade.
When does the Nichirin Blade turn “crimson red”:
A nichirin blade exceeds its powers and capabilities when it turns crimson red. This is different from the usual red of the nichirin blade of a Flame Hashira.
The main factor in triggering the change is increasing the temperature of the blade. This can be done in three ways:
- Firstly, if a user grips their sword and pours all their strength into the nichirin sword it can turn red. The strength of the user results in the blade’s temperature rising.
Obanai mentions that the blade turns red when the user is “pushing himself to the brink of death”.
- Secondly, if a user creates friction between their weapons it can also result in the blade turning crimson red due to heat.
- Lastly, we see Tanjiro use Nezuko’s Blood Demon Art to set his sword on fire, giving it the temperature it needed to turn all red.
A demon slayer mark is essential for using the first two ways.
Yoriichi Tsukiguni was the first demon slayer to activate the crimson red nichirin blade.
This nichirin blade can prove extremely dangerous to demons as it can hamper regeneration and also burn their cells. Kokushibo firsthand experienced the strength of a crimson red blade, describing it as feeling like his insides were seared.
Are Nichirin Blades real?
There are no historical accounts of colour changing blades, and as mentioned above, the only reference in the making of the nichirin blade is the Hihi’irokane ore.
However Proplica, known for making life size versions for sale from any other popular animes and mangas, have released real life nichirin blades!
It started off with Tanjiro’s katana getting forged, and the collection now also includes Rengoku Kyojuro and Kocho Shinobu’s swords.
Not only are they made with the utmost care about the details, they come with an audio feature which voices the characters’ iconic lines.
For the other characters, there are plethora of videos on YouTube that show fans recreating the weapons!
what about lavender blue