Logically he must've. People like Yamato and Shanks picked up Kaido/Roger signatures and both weren't even real students. Kuzan directly trained and learned everything haki related from Garp.
He should definitely have at least one Impact named move. Maybe Oda is saving that.
He should definitely have at least one Impact named move. Maybe Oda is saving that.
He builds up the power of his fruit, and at the right moment - BAM!
Hits 'em with a punch that freezes opponents to the core first only for the impact to completely annihilate their frozen body seconds later.
That might also work if Kuzan is secretly still with the WG working to assassinate Teach, it's his ace in the hole.