Only the best Swordsmen in One Piece can blacken theirn blades. Zoro will be able to achieve that before the end of the ...

Because like Luffy, Zoro has a way to literally get under Kaido’s skin thanks to the additional power granted by Oden’s former sword Enma given ... they both pose a major threat to him should ...

Zoro can go on to become an individual like the Sword God from long ago ... which is the biggest challenge that Elbaf poses to him. If I keep using Haki at this level, I'll die!

Given that all these swords are very powerful ... Hopefully, the challenges that Elbaf poses for Zoro will be enough for him to be pushed to the extreme and blacken one of his mighty blades.