As we were told in Zoro’s flashback of Kozaburo, there are no cursed swords, just swords with strong personalities. Based on Zoro’s difficulties in his fight against King, it it heavily implied that in order to bring out the full capabilities of a blade, you need to have the respect of the blade. Considering each blade has a unique personality, mastering one sword should be completely different from mastering a different sword.

In Zoro’s case, he imbued Conqueror’s Haki into the blade as a way to “conquer” Enma’s personality. However, I don’t think that was the end of it. Enma is named after the King of Hell and is stated to be able to “cut through to the bottom of Hell”, so maybe the way to master Enma (and possibly turn it into a black blade)… is to just straight up die?

Oden was probably one of the strongest swordsman we have seen in One Piece, yet he couldn’t turn his blades black. Then again, he wasn’t in possession of his blades when he died, so this could explain their un-blackened state. Even if he was holding them, Oden’s death was so sure (a shot to the head after being boiled alive) that he wouldn’t have survived to reap the rewards of conquering his blades.

Zoro, on the other hand, has not been dealt a finishing blow and is likely only having a brush with death at the moment. Maybe if he prevents the literal King of Hell from taking his soul, he can be considered worthy of mastering Enma. After watching the end of Thriller Bark and having witnessed his sheer willpower, I think it is likely that Zoro walks away from this encounter with death.

In general, I think that the name of a sword may also have something to do with its method of being mastered. Durandal (Cavendish’s sword) means “hard” or “unyielding” sword, and we saw Cavendish momentarily dispel Hakuba (which I predict is the personification of Durandal) by becoming unyielding and telling him “you should know to obey my orders”.

Shusui means “Autumn Water”. I won’t pretend to know the specifics of this one, but the sword belonged to Ryuma (a Shimotsuki), and Yasuie Shimotsuki ruled over Hakumai, which is an autumn island in Wano, so maybe mastering the blade had something to do with where the sword was forged (JUST A GUESS!).

Law’s sword, Kikoku, means Oni Wail, implying it may be conquered by defeating an oni (Kaido). Yoru (Mihawk’s sword) will have to wait for the end of my theory/Pepe Silvia-esque rant.

On top of this, I think that mastering a blade/interacting with a blade’s personality has already been shown in specific instances already and may have something to do with the mysterious Hawk-Eye. Basically, I think that when a sword and it’s wielder are in sync (when a blade is mastered), the wielder obtains the Hawk-Eyes. The Hawk-Eyes contain two yellow Irises, whereas a normal eye only has one Iris. This could imply two personalities being present at once.

One interesting occurrence of these eyes is when Cavendish and Hakuba shared a body in Dressrosa. Hakuba is probably the personality of Durandal (Cavendish’s sword), which makes sense as “Cavendish’s” sword skills are much stronger when Hakuba takes over. Cavendish himself never displayed two Irises on his own, and neither did Hakuba when he took over during the Coliseum fight. However, when Hakuba and Cavendish each controlled a half of Cavendish’s body at the same time, each side had two Irises.

The only problem is that the eye colors were different (in the anime), which I think implies that true mastery of the sword Durandal had not occurred. The fact that Cavendish had to fight Hakuba’s side of his body to protect Robin shows that cooperation was clearly not taking place, but since two personalities were present at the same time, the number of Irises changed.

Now on to Mihawk, who seemingly has the Hawk-Eyes 24/7. Before I get into his eyes in particular, I want to discuss Zoro’s “missing” Left Eye. I think that his missing eye is part of his training to create a black blade and become a master swordsman. As has been stated in Wano (in a conversation between Hyogoro and Kawamatsu), Ryuma was a one-eyed swordsman.

Ryuma also had a black blade, though we have conveniently never seen his actual eyes before (not counting in Oda’s One Shot “Monsters”). In One Piece, we have only seen Ryuma in silhouettes and as an eye-less zombie in Thriller Bark, so we can’t confirm if he had the Hawk-eyes. Based on all of this information, I believe that it is far easier to initially share the personality of your blade if it has a useless body part to enter.

In Hakuba’s case, he takes over Cavendish when he is asleep (when his whole body is not in use). When he entered his half-asleep mode, Hakuba took over half of his body. Maybe Ryuma had a damaged eye (as he was a one-eyed swordsman) and realized upon mastering Shusui that allowing his blade’s personality to manifest in his useless eye eased the process of sharing an entire body with it. This process may have been known by Mihawk, the greatest swordsman, and he passed the strategy on to Zoro, knowing that it would help Zoro down the road to have a useless eye (a vessel in a way) to house the personality of his sword.

Finally, let’s talk Mihawk. He shows no signs of eye injury, meaning he likely didn’t resort to purposely damaging an eye to master Yoru. To begin theorizing Mihawk’s method of mastery over Yoru, we will look into the meaning of his sword’s name: “night”. Night likely points to darkness, which can be interpreted metaphorically or literally. Personally, I think that Mihawk was born blind and thus mastering Yoru was easier, as darkness was already a part of Mihawk’s existence. Mastering Yoru gave life to his eyes by allowing Yoru to manifest in them. This would explain his eyes having been useless despite him having no visible scars. When he is in sync with Yoru, his eyes become functional, which is why he is always seen with the Hawk-eyes.

This unexpected background for Mihawk would parallel so well with Zoro’s past experiences, namely Kuina’s insistence that being a woman was a handicap that made being the world’s strongest swordsman impossible. Mihawk, a [theorized] blind person, became the world’s strongest swordsman, and Zoro would have had to come to terms with the fact that Kuina (someone he never managed to defeat) was foolish to give up on her dreams for such a poor reason.

I guess this is the end of my long-winded, broad theory on how a sword is mastered. Let me know what you think!

Theory by br4d1cal (