So first of all, I just wanna say that this is just pure speculation as I don't really have solid evidence to back up this theory. I just think it would be a very cool concept and scenario. Also English isn't my mother tongue so I apologize if there are some parts that isn't clearly explained.
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As the title implies, I believe Zoro will eventually succumb to a curse inflicted by his cursed blade, Sandai Kitetsu, which will happen in Elbaf.
1. The Dormant Curse and the Mystery of the Left Eye
For several years, the Sandai Kitetsu has been described as a cursed sword, yet we have never actually seen it curse Zoro. Even when he first acquired it in Loguetown, he threw it into the air and tested if it would cut his arm, and nothing happened.
So, you might be wondering: Why would it curse him now?
Actually, I believe the curse already happened during the timeskip. Ever since then, Zoro has sported a mysterious scar over his left eye, and the reason behind it has never been officially revealed. When you look closely, his left eye scar is on the exact same side of his body where he traditionally keeps and draws his Sandai Kitetsu.
This led me to a wild idea: What if the scar on his left eye was actually caused by the Sandai Kitetsu?
Perhaps during his rigorous training with Mihawk, the Sandai Kitetsu suddenly acted up, attempting to curse or possess Zoro. In a desperate struggle to suppress the blade's overwhelming bloodlust, Zoro fought back and accidentally ended up slashing his own left eye.
2. The Catalyst: Conqueror's Haki
If that’s the case, why isn't the sword constantly cursing him now?
I believe there is a specific catalyst that causes the Sandai Kitetsu to act up and that is Conqueror's Haki. We already know that Enma aggressively drains and feeds on Zoro's haki. Therefore, it would make total sense for the Sandai Kitetsu to feed on Conqueror's Haki as well.
And you might wonder why it didn't act up during Wano? Well, because Enma was aggressively draining and hogging all of Zoro's haki, the Sandai Kitetsu simply didn't have enough haki left to awaken and act up. But because Zoro's conqueror's haki got stronger in Elbaf, there's finally enough overwhelming willpower and energy to spare, allowing the Sandai Kitetsu to wake up and trigger that dormant curse once again.
Why Conqueror's Haki?
A person's supreme will to conquer naturally resonates with a cursed sword's bloodlust and its primal will to slaughter enemies.
3. Mihawk's Role and the Path to a Black Blade
Perhaps during his training on Kuraigana Island, Zoro accidentally unleashed his Conqueror's Haki, causing the Sandai Kitetsu to lash out and curse him.
This might also explain why Mihawk didn't explicitly teach Zoro about Conqueror's Haki. Maybe Mihawk wanted Zoro to discover it on his own, forcing him to face the dangerous consequences of unleashing supreme willpower while wielding a cursed blade. It is even possible that Mihawk faced a similar trial with his own sword, Yoru, in the past.
Ultimately, overcoming this curse could be the final key for Zoro to permanently turn his swords into Black Blades.
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As the title implies, I believe Zoro will eventually succumb to a curse inflicted by his cursed blade, Sandai Kitetsu, which will happen in Elbaf.
1. The Dormant Curse and the Mystery of the Left Eye
For several years, the Sandai Kitetsu has been described as a cursed sword, yet we have never actually seen it curse Zoro. Even when he first acquired it in Loguetown, he threw it into the air and tested if it would cut his arm, and nothing happened.
So, you might be wondering: Why would it curse him now?
Actually, I believe the curse already happened during the timeskip. Ever since then, Zoro has sported a mysterious scar over his left eye, and the reason behind it has never been officially revealed. When you look closely, his left eye scar is on the exact same side of his body where he traditionally keeps and draws his Sandai Kitetsu.
This led me to a wild idea: What if the scar on his left eye was actually caused by the Sandai Kitetsu?
Perhaps during his rigorous training with Mihawk, the Sandai Kitetsu suddenly acted up, attempting to curse or possess Zoro. In a desperate struggle to suppress the blade's overwhelming bloodlust, Zoro fought back and accidentally ended up slashing his own left eye.
2. The Catalyst: Conqueror's Haki
If that’s the case, why isn't the sword constantly cursing him now?
I believe there is a specific catalyst that causes the Sandai Kitetsu to act up and that is Conqueror's Haki. We already know that Enma aggressively drains and feeds on Zoro's haki. Therefore, it would make total sense for the Sandai Kitetsu to feed on Conqueror's Haki as well.
And you might wonder why it didn't act up during Wano? Well, because Enma was aggressively draining and hogging all of Zoro's haki, the Sandai Kitetsu simply didn't have enough haki left to awaken and act up. But because Zoro's conqueror's haki got stronger in Elbaf, there's finally enough overwhelming willpower and energy to spare, allowing the Sandai Kitetsu to wake up and trigger that dormant curse once again.
Why Conqueror's Haki?
A person's supreme will to conquer naturally resonates with a cursed sword's bloodlust and its primal will to slaughter enemies.
3. Mihawk's Role and the Path to a Black Blade
Perhaps during his training on Kuraigana Island, Zoro accidentally unleashed his Conqueror's Haki, causing the Sandai Kitetsu to lash out and curse him.
This might also explain why Mihawk didn't explicitly teach Zoro about Conqueror's Haki. Maybe Mihawk wanted Zoro to discover it on his own, forcing him to face the dangerous consequences of unleashing supreme willpower while wielding a cursed blade. It is even possible that Mihawk faced a similar trial with his own sword, Yoru, in the past.
Ultimately, overcoming this curse could be the final key for Zoro to permanently turn his swords into Black Blades.