12.01. Fixed Shooter
Fixed Shooters are those in which the player character moves along a single axis and fires shots to defeat waves of enemies.
History
Prototypes
Space Invaders
Space Invaders (Taito, 1978)
Evolution
Downturn
Fixed Shooters left as quickly as they came. By the mid-1980s, mainstream developers were no longer making Fixed Shooters from scratch. Instead, they had moved to the more flexible formulas of Tube Shooters, Area Shooters, V-SHMUPs, and so on.
Fixed Shooters continued to retain some relevance through relatively frequent re-releases of the two most popular entries: Space Invaders and Galaga. These entries generally only add new scoring modes or visual flair rather than significant iterations of gameplay.
Super-Subgenres
Gallery Fixed Shooters
The Gallery Fixed Shooter is relatively rare, though quite a few entries released between 1988 - 1990. It takes cues from the Gallery Shooter subgenre, with enemies appearing anywhere on screen and a more flexible reticle. However, this is merged with the player controlling a hitbox restricted to movement along one axis.
(video to go here for examples: Cabal, NAM-1975, Wild Guns, Bot Vice)
Alternates
The limitations of Fixed Shooters, as well as their short time in the limelight, means there are not many alternates to be found. The most common is the Isometric Fixed Shooter, which generally follows the same formula but with the screen slightly tilted:
Radar Scope (Nintendo, 1980); Juno First (Konami, 1983)
Beyond that, Charge 'n Blast (Sims, 2000) provided a 3D perspective:
The only Fixed Shooter with a gameplay modifier I have found so far is Konami's Block Hole (1989), which adds Tetris-like Puzzle elements.