Chapter 1010 confirms that Zoro will use Conqueror’s Haki to forge his Black Blades?


With the revelation of Kaido who believes Zoro has Conqueror’s Haki (possibly implying that Asura is a manifestation of it), I have been thinking heavily about how this could tie into the One Piece lore surrounding Black Blades A.K.A. Kokuto.


What we know about Kokuto at this time is limited, but includes the following:

  • A sword that has a black blade, having been turned black through countless battles.
  • It is stated that should a swordsman turn their swords into a Kokuto, then the grade of the sword could increase in Quality rank, but this is rare.
  • Quality rank in this case refers to the ‘Grade’ of a Named Sword or Meito. There are three Grade levels, and currently there are 83 swords that are graded:
  1. 12 Supreme Grade swords (including Mihawk’s Yoru)
  2. 21 Great Grade swords (including Wado Ichimonji, Shusui, and Enma)
  3. 50 Skillful Grade swords (including Sandai Kitetsu).
  • Yoru and Shusui are both Kokuto.

Now before I go into my theory… let’s review some of the history of various swords in One Piece. Particularly, I want to focus on three of Zoro’s most famous swords. Sandei Kitetsu, Shusui, and the recently acquired Enma.


Sandai Kitetsu was introduced to us very early in the series and it came with an ominous moniker of being a Cursed Sword or a Yoto. As a Yoto, it is known for bringing misfortune to its wielders. The Kitetsu swords in particular are known to cause their wielders deaths. When Zoro acquired Sandai Kitetsu, he put his luck against the swords curse and came out on top. An impressive feat that the shopkeeper who witnessed it gave his family’s heirloom Meito, Yubashiri, to Zoro as the feat rekindled his faith that true swordsman still exist.

Sandai Kitetsu’s cursed nature had been a very central theme when Zoro first acquired the sword. He had commented before that it was a ‘problem child’ and that it was ‘bloodthirsty’. He could even tell when it was nearby because he could sense the cursed energy from afar. Furthermore, Zoro has also implied that Sandai Kitetsu has tried to make his arm move without his direction which implies he has needed to fight the sword’s will to control his actions. This is an interesting theme with this cursed sword, and the idea of a sword attempting to control the action of it’s wielder will be re-visted with Enma.

But first, let’s move through this chronologically and discuss Shusui – our first real introduction in a Kokuto.

Shusui became a quick fan favorite because of it’s beautiful design not just as a black blade but the aesthetic of both the hamon and the scabbard. Shusui was inherited by Zoro at Thriller Bark from the zombie of it’s prior wielder, Ryuma, after defeating him in battle. From what we have gathered, Ryuma had been the one to turn Shusui into a Kokuto because we were told by Gyukimaru that Shusui was not always a Kokuto, but that it became one after many battles alongside its master.

Zoro first got to test the strength of Shusui’s blade out in the battle against Oars and he immediately was astounded by the strength of the blade when using it with Wado Ichimonji and Sandai Kitetsu to perform the Hyakuhachi Pound Ho (108 Pound Phoenix). The force of the Shusui’s shock wave absorbed the shock waves from the other two blades to create a singular, more devastating attack. It also is stated and shown to be incredibly durable whether it be by Zoro commenting that even if a dinosaur stepped on it, the blade wouldn’t bend an millimeter or how it has been used to block attacks from Oars and Neptune. Shusui after timeskip also became Zoro’s preferred blade for all Ittoryu attacks he uses, an acknowledgment by Zoro that is simply a superior blade in terms of power and durability compared to Wado Ichimonji despite them being of the same ‘Great Grade’.

It is worth noting that Zoro also called Shusui a ‘problem child’ before too, and that it had a temper which made it harder to wield. However, unlike Sandei Kitetsu or Enma, it is not shown to be as malicious towards Zoro. Merely that it is a challenge to wield.

One final note before moving on from Shusui: the fact that a Kokuto is shown to be so notably superior in performance compared to another Great Grade sword is something to keep in mind for when we get to the core of this theory.

Compared to the other two sections, Enma‘s will be more brief simply because our knowledge about it is rather limited still. But here is what we do know.

Interesting Detail on the Names given by Oda to Advanced Conqueror’s Attacks

Conqueror’s Haki as “The Embodiment of the Spirit of the User”