Dual Ki First Use Counterpart Dual Ki is the general term used for Martial Artists that have unlocked both Kis of Dou and Sei. Dual Ki martial artists have the ability to fight using either or both types of Ki. Most of the Dual Ki fighters specialize in only one of the two types despite being able to use both. The only Dual Ki martial artists that use both of them while fighting are the Elder of Ryōzanpaku; Hayato Furinji and Ogata Isshinsai. Ogata Isshinsai has so much control over his dual ki that he was able to develop and create a technique that uses both Ki's at once and amplifies it, calling it Seidou Gōitsu.