Galaga is a fixed shooter arcade game, and the sequel to Galaxian. Controlling a starship, the player is tasked with destroying the Galaga forces in each stage while avoiding enemies and projectiles. The player mans a lone starfighter at the bottom of the screen, which must prevent the Galaga forces from destroying all of mankind. The objective of each stage is to defeat all of the Galaga aliens, which will fly into formation from the top and sides of the screen. Aliens will dive towards the player while shooting down projectiles; colliding with either projectiles or aliens will result in a life being lost.