Webzenitsu uses thunder breathing.
The user takes out their katana and sprints at blinding speeds to decapitate their opponent.
Learns the thunder breathing technique from his teacher, jigoro kuwajima, focusing on its first form, thunderclap and flash.
The form consists of 6 styles initially, but *spoiler.
Zenitsu and the other 5 thunder breathing forms.
This post contains spoilers so read at your own risk.
As we all know zenitsu is capable of.
Webour view on zenitsu changed completely in season 1, episode 12, when he killed the tongue demon with the first form of thunder breathing: