The player is meant to explore large 2D game worlds and interact freely with the surroundings and inhabiting creatures. The game worlds are collages of well-known vintage video game genres, sometimes even juxtaposing contradictory "game modes", like side scrolling, top-down dungeon crawler or isometric pseudo 3D, creating bizarre and confusing scenarios.The possibilities for musical discovery are manifold: everything the player touches will either create new sounds or change the overall sound of the environment. There are many autonomous non-player-characters which the player can interact with in various ways, leading to suprising musical patterns. Furthermore, the author intentationally kept certain glitches and loopholes in the game architecture ("easter eggs") which can be discovered by the curious player.game_over was developed within the artistic research project "GAPPP" at the Institute of Electronic Music in Graz, Austria and was funded by the "österreichische Wissenschaftsfond". It has won the "Student Award for Excellence in the Application of New Technologies in Sound Art and Sound Design" at the international symposium "klingt gut! Symposium on Sound" in Hamburg, Germany, and has been presented at the international conference NIME 2018 at Virginia Tech, USA.