Sanji and Ichigo's battle was a battle of speed and intelligence.
Zoro and Sasuke's battle was a battle of techniques and Willpower.
Sasuke's eyes were constantly bleeding because of his overuse of Mangekyo Sharingan's visual power.
But since his chakra and visual power were recovering rapidly, he was able to constantly use his Susanoo to fight Zoro.
Every strike he launched could cause a catastrophic impact, but Zoro was able to take his attacks rather easily.
With his sword clad in Armament Haki, Zoro was able to defend against every attack that Sasuke threw at him.
With his Conqueror Haki, Zoro was able to launch attacks that could destroy his Susanno.
While Zoro didn't have a speed advantage, he was capable of overpowering Sasuke quite easily.
But there was one major problem.
Since Sasuke's Chakra and visual power could recover in the middle of the battle, Sasuke was able to keep Zoro far away from him.
Because of his Amaterasu.
Unlike in his world, where one could use Substitution, clone Jutsu, or chakra cloak to make Amaterasu ineffective.
Here, Zoro could only rely on his Future Sight to predict where Sasuke would use Amaterasu and dodge it in advance.
In fact, when Zoro faced the black flames for the first time, his Observation Haki gave him an intense warning, forcing him to use every bit of strength he could gather to dodge the attack.
Only then did he find that the black flames wouldn't go out until they burned their target.
Just to make sure it was really that powerful, Zoro even clad a stone in Armament Haki and used it to touch the black flames.
Amaterasu couldn't burn the Armament Haki. Its ability to withstand the temperature of Amaterasu was impressive.
But the moment he stopped channeling Haki, Zoro found that the stone started burning and turned to ash fairly quickly.
This made Zoro realize the power of these flames. While he could stop their influence with his Armament Haki, he couldn't do it indefinitely.
Unlike his enemy, his Haki and Haki wouldn't be refueled.
That meant if he got in contact with Amaterasu, he was done for.
Because of this, he wasn't able to close the distance between him and Sasuke without taking a powerful risk.
'This can't go on forever. I need to find a way to launch a final blow.'
Zoro thought to himself as he looked at Sasuke from a distance. His abilities were completely countered.
Even with his Future Sight, he wasn't able to catch Sasuke off guard.
Unlike Sanji, he had practiced all three forms of Haki to their advanced forms, allowing him to dominate Sasuke in a normal battle.
But the moment Sasuke would use his Amaterasu, Zoro had no choice but to retreat and use flying slashes to create distance between them.
'What can I do? What can be enough to kill him with a single strike?'
Zoro thought to himself as he launched two flying slashes.
On the other hand, Sasuke used the arrows of his Susanno to destroy the slashes mid-air.
What Zoro didn't know was that Sasuke was in despair.
When Sasuke was chosen for this battle, he was given a choice.
A choice to return to the past before Itachi destroyed his village with the full power of his current-self.
While his young body might be able to handle such power for a long time, just a few minutes would be enough for him to defeat Itachi.
Dojutsu, while awakened the moment of their awakening couldn't be used instantly.
Dojutsu like Susanno required a lot of training. If he returned to the past, with his mastery of Susanno, he would be able to defeat Itachi rather quickly.
With his strength, killing Danzo wouldn't be much easier.
After all, he knew everything about Danzo.
He didn't care about the Third Hokage because if he dared to obstruct him, he planned to kill the Third Hokage as well.
That's because once he returned to the past, his Mangekyo Sharingan would be as normal as they could.
That gave him enough confidence to face Itachi and Danzo, and even that Masked man.
He knew that man was also involved in the Uchiha Massacre.
So, this battle wasn't just a battle for him. It was his chance of fixing everything.
That's why he was desperately using his Mangekyo Sharingan to fight Zoro and defeat him.
But this also caused a problem for him.
While his Chakra and visual power were recovering, every time they recovered, he could feel his Chakra Reserves and visual power reserve getting smaller.
Chakra was a mixture of physical and spiritual energy. During this battle, he was constantly consuming both.
While this place could recover his Chakra, it wouldn't recover his physical energy and spiritual energy.
Because of that, he would constantly produce less and less Chakra. The more he recovered, the less reserve he would have.
This was bad for Sasuke, so his only choice was to finish the battle as quickly as possible.
But Zoro wasn't an idiot. As soon as his Observation Haki gave him any sort of warning, he would instantly back away as far as he could.
After all, except for Amaterasu, Zoro didn't have anything to fear about Sasuke.
Even his Susanno arrows coated with Amaterasu, Zoro was able to deflect with his flying slashes.
As someone close to approaching Admiral level with his Advanced forms of Haki, Zoro was far superior in his attacks.
Even Sanji's strongest attack before he mastered Advanced Conqueror was weaker compared to Zoro's flying slashes.
Of course, that's only when Zoro coats his swords with advanced forms of Conqueror and Armament Haki.
'I need a stronger attack to finish him. But it not only has to be strong but also fast. My Susanno arrows aren't capable enough.'
'It seems like I can only use that move, but he will definitely sense it with his sensory ability.'
'So, how do I hide it?'
Just as Sasuke was thinking about that move, he noticed several clouds forming above another battlefield.
His eyes lit up, but he kept a blank expression.
'That's great! With so many clouds, I can fire some of my fireballs to condense more clouds near me.'
He didn't just think about it. He started attacking Zoro with various Ninjutsu.
[Chidori Sharp Spear]
[Chidori Current]
[Phoenix Fire Jutsu]
[Fireball Jutsu]
[Chidori]
Different Jutsu made the battlefield tremble with lightning and fire. Each time Sasuke launched Chidori, the sound of a thousand birds rang.
Every time he launched a fireball, several explosions would occur.
Throughout the entire assault, Zoro did nothing but swing his sword.
Fireball? Cut it with a sword!
Chidori Sharp Spear? Block it with a sword!
Chidori Current? Destroy the ground with the sword so the current wouldn't reach him!
Multiple fireballs? One tornado created by three swords!
Chidori? Blocked it with a sword!
No matter how many Jutsu Sasuke threw at Zoro, it would always get blocked by Zoro's sword.
This was exactly why Sasuke wanted to finish this battle as quickly as possible.
While he could recover, his reserve was getting smaller and smaller.
This was bad for a battle of attrition. So, Sasuke had no choice but to finish Zoro with a single Jutsu.
But Zoro wasn't idiot enough to touch Amaterasu. If his Future Sight saw Sasuke use Amaterasu, he would create a gap without much hesitation.
His goal wasn't just to win. It was also to survive. He still had to help his captain.
Because of this, their battle was basically a stalemate until Sanji created those clouds.
The moment Sasuke saw those clouds, he started recruiting them near him using his fireball Jutsu.
The more clouds he gathered, the greater the threat Zoro perceived. But he didn't know where the danger was coming from.
Sure! Future Sight was amazing, but Sasuke hadn't guided the attack.
And, it wasn't like Zoro could see ten seconds into the future. At best, Zoro could see for two seconds.
And, that's only when he was keeping full concentration; otherwise, his Future Sight would only give him the vision of one second into the future.
That's why, despite perceiving danger, Zoro didn't know where the danger was coming from.
Until he noticed an abnormally high number of clouds above them.
'No, these aren't cook's clouds. They are his.'
The moment Zoro found that, Sasuke noticed his expression through his Sharingan and immediately jumped as high as he could.
He raised his hand towards the sky, and a large number of lightning bolts started gathering above him.
"This is where it all ends. Disappear with the lightning!"
[Kirin]
At this moment, a massive lightning dragon head emerged in the sky. Even Naruto and Luffy looked over in surprise.
On the other hand, Sanji also saw this, and his expression darkened. Because he realized he had inadvertently helped his adversary.
But then, a smirk appeared on his face.
"You want to defeat Mosshead with such weak lightning? Dream on!"