Galaxia is an arcade style shooter. You control a spaceship and need to earn as many points as possible by shooting the various enemies that appear on the screen. Unlike many similar games (such as Demon Attack or Phoenix) your ship can move about the entire screen and is not limited to horizontal only movement. On each level has there is a timer, if time runs out and you haven't finished destroying all of the enemies, the next level will begin, however all of the remaining enemies from the previous level will remain on the screen (so you now have two sets of enemies to destroy at once). There are many different types of enemies to destroy which become faster and more numerous as the levels progress.