Opus: Echo of Starsong (stylized as OPUS: Echo of Starsong) is a text-driven side-scrolling adventure game developed by Taiwanese independent studio SIGONO. It is the third installment of the Opus series after Opus: The Day We Found Earth and Opus: Rocket of Whispers. Like its predecessors the game focuses on story puzzles and exploration. The game was released for macOS and Windows on September 1 2021 to strong critical reception. An enhanced version with voice acting titled Opus: Echo of Starsong - Full Bloom Edition was released for Nintendo Switch on May 11 2022 as an update for macOS and Windows on May 19 2022 and for Xbox One and Xbox Series X/S via Xbox Game Pass on August 25 2022. A mobile version was released for iOS on November 17 2022.