Galaga features a spacecraft called the Fighter that can be upgraded by rescuing a captured ship.
Namco released Galaga in 1981 as a sequel to Galaxian. The player controls the Fighter at the bottom of the screen and battles formations of alien Galaga creatures. A captured Fighter can be recovered when the player destroys the enemy holding it.
When the rescued ship joins the original, the player gains a dual Fighter with increased firepower. This mechanic is one of Galaga’s most recognizable features and distinguishes it from many other fixed shooters.
Galaga is sometimes confused with Galaxian because both use alien formations and vertically oriented playfields. Galaga adds more elaborate enemy movement, tractor-beam captures, bonus stages, and the possibility of doubling the player’s ship.