Enma is literally Oden's blade and it made Zoro use ACoC. I'm talking about showing it on panel.
You can't assume no leaking curved Haki = no ACoC.
You can't assume no leaking curved Haki = no ACoC.
And you can literally see lightening coming out of Kaido showing CoC.
CoC is shown by lightening
Zoro scarred Kaido with CoA only