Ryoku ranks among the Seven Sages of the villainous Team Plasma. He appears in the Pokémon Generations animated short "The Uprising," present at N's Castle during its emergence around the Unova Pokémon League. There, he engages in discussions with fellow sages regarding fate, justice, and Team Plasma's impending rule over Unova under Ghetsis's command. In the core series games Pokémon Black and White, Ryoku first confronts the player at Relic Castle, declaring Ghetsis ordered him to test the player's strength. He later stands with the other sages at N's Castle, blocking access to N until Gym Leaders intervene to clear the path. After Ghetsis's defeat, Ryoku returns to Relic Castle attempting to capture Volcarona as a gift for Ghetsis. Learning of Ghetsis's disappearance, he voices disillusionment with Team Plasma's ideals and questions the purpose of the Seven Sages' unity. He relinquishes TM04 (Calm Mind) to the player before his arrest by Looker. Within the Pokémon Adventures manga, Ryoku's history stretches back three years prior to the main events, when Ghetsis tasked him with locating and protecting Volcarona from humans. He secures Volcarona within Relic Castle and delivers its egg to the Shadow Triad. During Team Plasma's takeover of the Pokémon League, he battles trainers aiding the protagonist Black using a Scolipede. Though Gym Leaders break free and confront the sages, Ryoku escapes. In the Black 2 & White 2 arc, he and fellow sage Bronius operate in Castelia Sewers, orchestrating a diversion for Team Plasma's operations. International Police agent Blake arrests them, but they express confidence their leader's goal succeeded. Ryoku's dialogue incorporates philosophical references. At N's Castle, the English versions feature him citing a proverb by Song Dynasty philosopher Hu Yin, while the original Japanese dialogue includes a quote from Zhuangzi. His name derives from the Japanese word for green (緑色, "ryokushoku"). This connection to green is mirrored in his international names across languages.