Chikao Otsuka was a highly esteemed Japanese actor and voice actor, whose career spanned over six decades from 1948 until his passing in 2015. Born on July 5, 1929, in Tokyo, he was affiliated with the talent agency Aoni Production at the time of his death. He is remembered as a foundational figure in the voice acting industry, renowned for his deep, distinctive, and often villainous or authoritative voice, which he lent to a vast array of iconic characters across anime, video games, and film dubbing. Otsuka passed away on January 15, 2015, due to ischemic heart failure at the age of 85.

Otsuka's career was marked by an extraordinary number of legendary roles. He was the original voice of Goemon Ishikawa XIII in the first Lupin III series, a role that established him as a major talent. He brought to life numerous other memorable characters, including the villainous Captain Hook in various adaptations of Peter Pan, the cunning Professor Moriarty in Sherlock Hound, the menacing Jagi in Fist of the North Star, the powerful Taopaipai in Dragon Ball, and the enigmatic Nezumi Otoko in multiple installments of the GeGeGe no Kitaro franchise. In the long-running series One Piece, he provided the voice for the legendary Pirate King, Gol D. Roger, a cameo role of immense significance to the series' lore. The example cited by the user, the role of Kuma-san in the 1982 sports anime special Two Down Full Base, is a testament to his early and versatile work in the industry.

Beyond anime, Otsuka was the definitive Japanese voice for several major video game characters. He is perhaps best known to gamers worldwide as the voice of the brilliant but rotund antagonist Doctor Eggman in the Sonic the Hedgehog series, a role he played for many years. He also portrayed the complex villain Master Xehanort in the Kingdom Hearts series and took on the role of the legendary soldier Big Boss in Metal Gear Solid 4: Guns of the Patriots. His filmography also includes voicing Dr. Cid in Final Fantasy XII, Jinpachi Mishima in the Tekken series, and Joseph Joestar in the 1993 JoJo's Bizarre Adventure OVA.

His legacy is also deeply connected to his family. He was the father of fellow renowned voice actor Akio Otsuka, and the two occasionally performed together in various works, including Mobile Suit Gundam 0083: Stardust Memory, the Full Metal Panic! series, and Metal Gear Solid 4, creating a unique and celebrated father-son dynamic in the industry. In addition to his animation work, Otsuka was the official dubbing artist for Western actors such as Charles Bronson and Richard Widmark, further solidifying his status as a premier voice talent in Japan. His immense contributions to the field were recognized with the Tokyo Anime Award for Animation Merit (Voice Actor category) in 2014. Even after his death, his performances continue to be heard in various media through archived audio, ensuring his iconic voice lives on for future generations.