After generating black lightning from their body, Darui releases it in the form a panther to shock anyone that comes into contact with it. Its quick movement allows it to be used to take out multiple opponents. By using this in a battle on water, it can be spread out to cover a wide range.
As with many of the techniques of Kumogakure ninja, this technique has an English name given kanji that somewhat match the pronunciation. Usually, the kanji would be pronounced as 'Kurohansa' or 'Kokuhansa'.