Mikio Terashima was a Japanese actor and voice actor born on September 4, 1931, in Fukui Prefecture. He passed away on December 4, 2008. Before entering the entertainment industry, he worked at a local company after high school before moving to Tokyo to pursue his passion for performance. His career began in theater when he joined the New Theater Research Institute in 1952, and he later became a founding member of the Shinen Theater company. Throughout his life, he considered himself first and foremost an actor, not just a voice actor, and was deeply involved in theater as a performer, director, and mentor, particularly in community and regional theater productions. He was affiliated with the Tokyo Actor's Consumer's Cooperative Society until his retirement in 2001.

Terashima's voice acting career spanned from the 1960s until his retirement, and he became known for his deep, powerful voice and his portrayals of villainous characters. One of his most iconic roles was that of the antagonist Berg Katse in the seminal series Science Ninja Team Gatchaman and its film adaptation. He also voiced another memorable emperor, Zu Zambajil, in Voltes V. His involvement in the Space Battleship Yamato franchise was significant, where he played Sho Yamazaki in several productions, including Final Yamato and Star Blazers: The Bolar Wars. He contributed to many other classic anime of the 1970s and 1980s, with roles such as Dr. Sanada and Zenigasky Jitter in GoShogun, Duke de Forge in Étoile de la Seine, Blaster 1 in Astroganger, Sone in Ninpu Kamui Gaiden, and Togashi in The Legend of Kentauros. His filmography also includes Genjuro Fujibayashi in The Dagger of Kamui, Kuwata in Angel Cop, and Coach Kunimasa in Shōri Tōshu, as well as Isao Egawa in Nozomi in the Sun.

Throughout his career, Terashima's distinctive voice was frequently cast in roles that demanded authority or menace. Beyond the characters listed in the query, his extensive body of work included roles in Ashita no Joe, Lupin the Third, and Devilman, among many others. He was also active in dubbing foreign films and documentaries, where his voice became associated with historical figures like Adolf Hitler. Terashima's legacy is that of a versatile and dedicated performer who was a cornerstone of Japanese popular culture in the postwar era, leaving a lasting impact through both his on-screen roles and his commitment to nurturing the next generation of theatrical talent.