Something interesting occurred to me now. Or maybe someone already mentioned it and I just remembered it now lmfao.
What if to achieve black blades, aside for amazing and strong haki, one needs to fulfill his will and the will in the sword?
Shusui became a black blade over the course of many battles in which Ryuma successfully defended the Wano nation, thus fulfilling his will and desire of protecting it.
Yoru became a black blade once Mihawk fulfilled his desire of becoming the strongest.
Enma will become a black blade once it slays Kaido, something both Zoro and Oden desire, hence Oden's will being in the sword.
Wado will become a black blade once Zoro fulfills his and Kuina's will and desire of becoming the strongest.
Kitetsu or X sword that Zoro ends up with is a question mark for now.
What if to achieve black blades, aside for amazing and strong haki, one needs to fulfill his will and the will in the sword?
Shusui became a black blade over the course of many battles in which Ryuma successfully defended the Wano nation, thus fulfilling his will and desire of protecting it.
Yoru became a black blade once Mihawk fulfilled his desire of becoming the strongest.
Enma will become a black blade once it slays Kaido, something both Zoro and Oden desire, hence Oden's will being in the sword.
Wado will become a black blade once Zoro fulfills his and Kuina's will and desire of becoming the strongest.
Kitetsu or X sword that Zoro ends up with is a question mark for now.