Dracule Mihawk is, of course, the world's greatest swordsman and is known as the most dangerous sword wielder in the One Piece world. While he'd probably be just as dangerous with a wooden toothpick, Mihawk prides himself on his mighty sword, Yoru, which is one of the most powerful swords in the series. But due to its black color, it's also one of the most remarkable. In this article, we'll tell you how Mihawk managed to turn his blade black in the series.

It is unclear exactly how Mihawk transformed Yoru into a black sword (Kokuto). One theory suggests that the sword was forged this way, meaning it was black from the start, but this is not very likely, as the process of transforming a blade into a Kokuto is known. Therefore, it is more likely that Mihawk simply blackened his blade through constant fighting and the fact that he learned to imbue his blade with Armament Haki, which is a very complex process but can directly lead a blade to become a black sword. This has not been officially confirmed in the series, but it is the most likely explanation.

The rest of this article will focus on Mihawk's blade, Yoru, and its color. We will tell you about the blade and explain, based on known facts and popular theories, why it is black, as it is not a very common and usual blade color. Official history has not really revealed the reasons for this, but we will try to combine what we know with what we can deduce from it to form a meaningful theory about the color of Mihawk's blade, as it is an extremely important question.

Unfortunately, the manga doesn't explain why Yoru is black, but we can come up with a pretty plausible theory.

Before we get into the theory, let's first talk a little bit about Yoru. Yoru is not only Mihawk's main weapon, but it's also one of the most famous swords in the entire series, given how powerful and notorious it is.

Of course, as we've said, Mihawk is just as dangerous with a toothpick as he is with a regular pocket knife. However, with Yotu, he can defeat anyone in a sword fight, and all this without any additional powers except his Haki. So, let's see what we can tell you about Yoru.

Yoru is Dracule Mihawk's black sword and one of the twelve Saijo O Wazamono quality swords. The sword has a white cloth-wrapped handle with an emerald pommel and a very wide golden cross-shaped hilt, which juts out into a ridge on the flat part of the blade, intricately decorated with reliefs and gemstones.

The blade is black with a strong sheen and curved towards the tip like the Kriegsmesser. It features an "irregular double-clove pattern," though it is not very visible. It does not have a scabbard, as Mihawk prefers to hang it behind his back using simple laces. The sword is very large, the blade alone almost as long as Mihawk himself, who is just under two meters tall.

Its owner defines it as the most powerful sword in the world, and as one of the twelve Saijo O Wazamono, it is a sword without precedent in terms of value and power. In the hands of the most skilled swordsman in the world, the Yoru becomes an incomparable weapon: Mihawk manages to create powerful flying attacks capable of cutting ships and ice mountains from a considerable distance, but also of deflecting projectiles with a slight movement of the sword.

Mihawk claims that his weapon has never even been dented, thanks to Armament Haki, which he imbues it with in battle.

It is unknown how long Dracule Mihawk has possessed the Yoru. However, it was not yet in his possession at the time of Gol D. Roger's execution. During his journey across the East Sea, Mihawk confronts and defeats Roronoa Zoro in a duel but urges him to continue improving until he can defeat him and his sword. Mihawk uses his sword to unleash powerful slashing blows against the Whitebeard Pirates, also managing to slice through a mountain of ice. He then engages in a duel with Luffy and then Vista.

If you've been paying close attention to the series, you'll have noticed that Yoru is black, which actually makes perfect sense since the word "yoru" (夜) means "night" in Japanese, and night is black, so... yeah. But, while it may seem like it's just a symbolic thing, there is an in-universe explanation for why Yoru is black. While we haven't seen it in the manga, based on what we know, we can come up with two theories about the blade's color.

The first theory is very simple and states that Yoru was a Black Sword from the beginning, meaning it was black when Mihawk received it. A black sword is not usually forged, as far as we know, but actually made, so this could mean that Mihawk received his sword after it had already been transformed into a black sword, but to be honest, it's not that we can't imagine a legendary-level black swordsmith in One Piece who could immediately forge a black sword. This theory, however, doesn't seem plausible, as there is a better and more user-friendly one that explains everything.

Of course, the theories that Mihawk is a fraud who simply painted his sword are absolutely ridiculous, so if you come across them on the internet (and you probably will, because they are out there), you can immediately ignore them.

So now that we've covered all that, let's explain the main theory that we think is probably true and accounts for every aspect of Yoru's story, including his color and Mihawk's status in the series.

Namely, if you are familiar with Armament Haki, you will also know that its hardening effect can be imbued onto weapons or other items to make them stronger and firmer, as hardening produces a black layer, weapons imbued with Armament Haki also turn black, this is how the weapons also turn black.

Now, if you do this for a long time and in many battles, we assume that your blade will consistently turn black after long exposure, and this theory really explains everything. It really does.

Now, we know that Dracule Mihawk is a strong advocate of constantly imbuing his blade with Armament Haki, and when Zoro trained with him during the time skip, he taught him how to master this technique. So we assume that Mihawk simply continued imbuing Yoru with Armament Haki until the blade turned black and remained so, even when it wasn't imbued with Armament Haki.