But you won't apply this to logic to the thread because you know it would expose this new cope of the week that Zoro didn't use KOH or advcoc against Nasujuro. Lol
I'm tired of explaining it.
You have to distinguish black rays that start from the impact point, which Oda uses quite randomly and without apparent coherence, with black trails that come from the parts/weapons imbued with AdvCoC.
That being said, the KoH is the flames + AdvCoC (black trails) and we didn't see that in Egg Head.
Also, if you don't believe me you can see that Zoro already had flames on his swords before creating the KoH, which appeared just when CoC woke up and the contrails appeared.
Edit: In addition to having the tagline En-Ou of course, which we haven't seen either.