OPUS Echo of Starsong — is a puzzle-solving and space exploration adventure game in which we accompany the two main characters in the extraction of a precious substance that is the source of numerous political conflicts, and reveal the secret that he and the entire universe are guards. The game was created and published by SIGONO INC, The studio responsible for the previous OPUS games, OPUS Rocket of Whispers and OPUS The Day We Found Earth. The game takes place in an alternate future where asteroids contain a mysterious substance called Lumen. It is so powerful that it has become the subject of controversy. In the game we play as Lee, a boy who was exiled by his people, and now he himself wants to take possession of Lumen in order to glorify his clan and join him again.