The sword is one of the weapons commonly used by various characters in the One Piece story . Starting from the protagonist, to the antagonist, there are many who use the sword as their main weapon. Examples are Roronoa Zoro, Big Mom, Shanks, and many others. And as presented in the story, there are three main categories of swords in the One Piece story.
The first is Meito. Meito can briefly be interpreted as a popular sword. Swords that fall into this category are swords that are very well known by many people. They would know the sword just by looking at it. Then the second one is Yoto. Yoto's sword is a sword that is both mysterious and cursed.
Yoto's sword is called a cursed sword because the user or owner will feel "side effects" from using the sword. As explained by Shimotsuki Kouzaburo in chapter 1033, that swords have their own personalities. And there is no such thing as a cursed sword. The wielder likely has a lower power than the sword so it is difficult to control it.
The last one is Kokuto or can be interpreted as a black sword. The black sword is probably the highest classification of these three, where not all swords can then fall into this category. In fact, the black sword actually cannot be obtained but is obtained by continuously using it.
The strong connection between the user and the sword is one of the keys to making a black sword. Tenguyama also explains that Haki is another key to being able to turn a sword into a black sword. So far, there are only two swords that fall into the category of black swords; Yoru and Shusui.
Yoru
Yoru is one of the 12 Saijo O Wazamono swords or swords of perfect quality. So far, only 3 swords shown in the story are included in the sub-classification of perfect swords, namely Yoru, Shodai Kitetsu, and Murakumogiri. In addition to being a sword with perfect quality, Yoru is also a sword that falls into the black sword category.
Yoru is a sword owned by Dracule Mihawk. This sword is shown to be very powerful, for example when splitting the ice waves during the great war at Marineford. The power of Yoru's sword has also been shown when Mihawk destroys a large ship with one slash. In fact, Mihawk is also shown to be able to destroy the meteors drawn by Issho with this sword.
It is still unknown where Mihawk got the sword, and also whether Mihawk got it from the start and then turned it into a black sword, or Mihawk found it already in a state of being turned into a black sword. We also don't know who made the Yoru sword.
Yoru's sword itself is known to have a height of more than 190 cm, this is because the sword is able to exceed Mihawk's height when stored behind. Mihawk himself is often seen using two hands to swing Yoru's sword, but what's amazing is that it's not uncommon for him to only use one hand as if Mihawk is used to doing it.
Shusui
Like Yoru, Shusui is one of the strongest swords in the series. However, what's interesting is that Yoru is not part of Saijo O Wazamono, but O Wazamono or a sword that has good quality. O Wazamono itself is one level below Saijo O Wazamono. And there are approximately 21 swords that fall into this sub-classification. Shusui is one of them.
The Shusui sword was once used by a legendary samurai, a figure who is considered a guardian deity for the people of Wano, namely Shimotsuki Ryuma. After his death, Shusui's sword was kept on Ryuma's grave. However, when Gecko Moria comes to Wano, he steals the sword along with Ryuma's corpse, which he uses to create an army of zombies.
The Ryuma zombies themselves have appeared in the Thriller Bark arc, where in Ryuma's zombie body there is a shadow of Brook. After winning the fight against Ryuma's zombies, Zoro finally got Shusui's sword because Zoro was considered a great swordsman who was considered worthy of being the new owner of Shusui.
The power of Shusui's sword has been shown several times, for example when Zoro destroys a ship with only one slash. Or when he used this sword against Pica. Also when Zoro used it against Oars. Although not part of the canon story, Shusui is the sword used by Ryuma to kill a dragon in ancient times.
A Sword That Has the Potential to Become a Black Blade
As mentioned above, that so far there are only two swords that are included in the black sword category. However, that does not mean that there are no more swords that have the potential to become black swords. As long as the requirements to be able to change an ordinary sword into a black sword can be fulfilled, then it is not impossible that another black sword will be born. Here are some swords that have the potential to become black swords:
Wado Ichimonji: Wado Ichimonji is one of the 21 swords with good quality. Similar to Shusui. This sword was originally a sword that would be passed down to Kuina, but Zoro then asked Koushiro to give it to him out of respect for Kuina. On several occasions, we see how this sword is powered by Haki, which means this sword has the potential to become a black sword in the future. Also this sword is made by Shimotsuki Kouzaburo who has a connection with Zoro.
Ame no Habakiri: This sword is also one of the O Wazamono swords or swords with good quality. This sword was previously used by Kozuki Oden, and before his death, Oden bequeathed this sword to Kozuki Momonosuke. This sword became one of the two swords that had hurt Kaido. Based on that, this sword could definitely become a black sword, and it was Momonosuke's job to do so.
Gryphon: Gryphon is a sword owned by one of the Yonko, namely Shanks. The classification of the Gryphon sword itself is still unknown until now. However, there is speculation that the Gryphon could be one of the 12 Saijo O Wazamono. Gryphons have also been shown to be coated in Haki, such as when resisting Sakazuki's attacks. This means that this sword has the potential to become a black sword. Being able to turn the Gryphon into a black sword would certainly suit Shanks' status as a Yonko.
Sword of Fujitora: Fujitora was the first naval admiral to be considered a navy with extraordinary swordsmanship. His sword -wielding ability is even able to surpass the swordsmanship ability of Roronoa Zoro. In fact, Fujitora was able to balance Sabo's ability. Fujitora has often coated his sword with Armament Haki. With his status as a swordsman, it is natural for Fujitora to be able to turn the sword whose name is not yet known into a black sword.
Enma : Like Ame no Habakiri, Enma is one of Kozuki Oden's swords. This sword originally belonged to Kozuki Hiyori, before Hiyori exchanged it for Zoro's Shusui sword. Enma is also one of the swords that fall into the subclassification of O Wazamono, and has a "tremendous" ability to absorb the user's Haki. According to Tenguyama, Zoro has the opportunity to turn him into a black sword, and at the end of chapter 1033 it is shown how Zoro's potential to turn Enma into a black sword has begun.
