Board Thread:Naruto Discussions/@comment-45851667-20200520192705/@comment-34656247-20200523203949


 * One usage is enough for it to be famous. For example: The samurai's seeing amaterasu for the first time would probably brag about it to other samurai's, and grapevine starts. So if one eye was used for it to be known, shisui was aware he couldn't use koto on that very eye again, so he was obviously going to use koto with the remaining eye on fugaku.
 * The wiki just states Genjutsu, Kotoamatsukami wasn't specifically stated in the novel either, so just base MS genjutsu.
 * You're ignoring the Hashirama cells on crow point. You're ignoring the eye merging.