Oguro Iwao

Iwao Oguro (雄 (お) 黒 (ぐろ) 巌 (いわお) , Oguro Iwao), also known as Knuckleduster (ナックルダスター, Nakkurudasutā), commonly referred to by Koichi Haimawari as Master (師匠, Shishō), is a Vigilante and a member of the Naruhata Vigilantes. He was formerly a Pro Hero; specifically the High-Speed Hero: O'Clock (超速ヒーロー・オクロック, Chōsoku Hīrō Okurokku) in Japan, and Hyper Quadfist (超 (チャオ) 頻 (ピン) 四 (スー) 拳 (チェン) , Chaopin sūchen) in China.