Tsuyoshi Koyama (小山 剛志, Koyama Tsuyoshi) is a Japanese voice actor and singer, affiliated with Across Entertainment, who voices Sports Maxx in the fifth season of JoJo's Bizarre Adventure: The Animation, Stone Ocean.
He is also known for his roles as the Beast Mercenary in Grimoire of Zero, Vassago "PoH" Casals in Sword Art Online, Kamen Rider Odin in the Kamen Rider series, Doc Louis in the Punch-Out!! and Super Smash Bros. series, and Bang Shishigam in the BlazBlue series.
Tsuyoshi Koyama was born on October 4, 1967 in Japan's Aichi Prefecture. He graduated from Waseda University at the age of 24 and began work as a stage actor. He made his anime role debut as Phil Ackerman in Turn A Gundam.
In 2007 he made his debut as a singer with the self-written self-composed song "Sin Utawarerumono Theme", which is used in a radio drama based on the visual novel game Utawarerumono and reached 10th on the Oricon Daily Ranking chart. He has since worked on various songs for the BlazBlue fighting game series.
On January 10, 2010 he began writing a blog titled Tsuyoshi Koyama's No Pain, No Life.
He started playing mahjong as a student in high school and in December 2015 he became began playing it as a side job, participating in various programs and projects involving it. He produced his own mahjong competition called Mahjong Octagon where even celebrities compete alongside professionals. When he moved to Shibuya in October 2016, Mahjong Octagon's operation was transferred to CyberAgent in July 2021.