Naruto Shippuden Ultimate Ninja Storm Revolution: Creation of Akatsuki, explains the origin of the Akatsuki. Obito one of his jobs is to make sure Itachi & Kisame join Akatsuki. in sequence the story, obito met Kisame on kisame's flasback [[1]].Obito still have long hair, a lot of people thought it was Madara, At that time Kisame Hoshigaki began to be disillusioned by the lies of the world. Obito (as "Madara") revealed himself to Kisame and promised to help make a world of truth. Kisame became his loyal servant. Previous, he came along Yagura "Fourth Mizukage" from darkness to be controlled by genjutsu. Yagura being controlled his mind (Obito was manipulating the Mizukage), I think it's sort of just like Dōjutsu Kotoamatsukami Shisui
(The technique allows the user to enter the mind of any individual within their field of view, and manipulate them by giving them false experiences, making it seem as if they were doing things of their own free will.)
what do you think, should we discuss now?
note: During the Five Kage Summit, the Fifth Mizukage (Mei Terumi) commented that she couldn't help but conclude that there was a connection between this technique and the power that controlled Yagura, the Fourth Mizukage.