It can not be Oden haki because that's not the way the sword works.
No, he doesn't need enma to control large amounts of haki.
He was able to take large amount of haki back from enma.
The Scabbards don't need enma or large amounts of haki to cut Kaido but Zoro does? Really?
When Kid hit Big Mom with his harpoons and it bounced off we see the hit marks above her body.
That tells is the attack bounced off her body.
When Zoro fought Kaido in asura mode we see hit mark to Zoro's right. It's not over his body. That means it deflected Kaido's club.
Similar to his battle against Hyouzou.
And the current clash between Kaido and Yamato.
No, he doesn't need enma to control large amounts of haki.
He was able to take large amount of haki back from enma.
The Scabbards don't need enma or large amounts of haki to cut Kaido but Zoro does? Really?
When Kid hit Big Mom with his harpoons and it bounced off we see the hit marks above her body.
That tells is the attack bounced off her body.
When Zoro fought Kaido in asura mode we see hit mark to Zoro's right. It's not over his body. That means it deflected Kaido's club.
Similar to his battle against Hyouzou.
And the current clash between Kaido and Yamato.