Oonoki is the current Tsuchikage of Iwagakure. As a young man, Ōnoki was a student to the Second Tsuchikage, Muu who taught him how to use the Dust Release techniques. Later in life, he himself would become a teacher to Deidara. Though he often implied that Deidara's ideologies and fighting style annoyed him, he was still proud of him. At some time in the past, Oonoki fought with Madara Uchiha, the only living Kage to do so. His knowledge of Madara's power made him wary of him, and was thus surprised that the latter would choose to carry out his designs behind the shadows through Akatsuki.
Oonoki is very proud but appears frail, with constant complaints referring to his hips and back. He also refuses to retire and choose a successor as Tsuchikage despite his frailty, insisting that he is still strong enough to continue to rule the village. Kurotsuchi describes him as a "stubborn old man". His pride has him give very little respect for those younger than him.
He is a powerful and capable Tsuchikage. He is physically frail, however, and as such he isn't suited for taijutsu fighting. He has a great deal of experience, having fought Madara Uchiha and survived, thus his knowledge is invaluable to the Allied Shinobi Forces.
