Danzo's right eye was implanted with a Sharingan plundered from Uchiha Shisui, which harbored the ultimate illusion known as Kotoamatsukami.
Possessing the heaven-defying ability to forcibly rewrite the wills of others, Kotoamatsukami was a tremendously powerful genjutsu, yet its cooldown period was agonizingly long. Even with Senju Hashirama's cells, which could shorten the cooldown to a certain extent, Danzo's pitifully few implanted cells were merely a drop in the bucket compared to Kotoamatsukami's cooldown of over a decade.
Consequently, Danzo had always kept Kotoamatsukami as his ultimate trump card.
Chapter 98