Horizontal Scrolling Shooter
A subgenre of the Shoot 'em Up
As the name suggests, the game's playfield constantly scrolls horizontally
over the course of a level. The view can either be side-on or top-down, depending on the developer's choice. The most common use of such an engine has been for games with some kind of spacecraft either flying over a landscape or through an installation, with unbreakable obstacles that would kill the player either on contact, or by blocking the craft.
Most such games had the player collect health, lives and weapons as powerups in the levels, although some allowed the player to make purchases with their points between levels.
Complexity varies by having different numbers of layers of parallax and in some cases, transparency effects, such as translucent explosions.
Compare Vertical Scrolling Shooter
. Horizontal Shooters tend to have more variety in power-ups and less difficulty, but these are far from being hard rules.