Galaga '90' is a single-player action shooter game in which players control the Triple Proton Fighter to combat waves of enemies. The core mechanics involve maneuvering the fighter across the screen and shooting down clusters of mutants and misfits that attack in swarms, utilizing enhanced firepower and dimensional warping features. In this game, the setting is a smouldering planet plagued by angry mutants and misfits, with players taking on the role of a Galactic commander of the Federal Army tasked with exterminating these threats. It stands out with its advanced gameplay elements such as dimensional warping, increased firepower, and the ability to navigate through different environments, providing a dynamic and challenging experience for players.