A stage element is simply any aspect of a stage. There are many kinds of stage elements, and they may exist conceptually, as events, or as tangible parts and their abstractions. A stage is typically made up of many elements, the most common of which are backgrounds, a large central platform, and edges. There are some things that appear during gameplay on stages that are not a part of a stage, such as characters and most items.
Some elements have virtually no impact on gameplay, such as the score on 75m, while others may aid players or are hazards. Some elements may even serve multiple roles, intentional or not, such as the Shy Guys on Yoshi's Island who may bring food or accidentally obstruct projectiles.
The elements in official stages cannot be removed or altered in any in-game way except those that are dependent on whether or not items are turned on. The Stage Builder in Super Smash Bros. Brawl introduced the first way for players to create their own stages, although all the provided parts (except for the theme and background) are exclusively tangible and there is no way to create abstractions or events.
List of stage elements
Note the following list contains superficial or tentative titles.
An event pattern is a stage element in Melee and Brawl that dictates the flow of other stage elements. There are a few basic types of event patterns - loops, cycles, rails, and random events - and at least one appears in every official stage and custom stage.
A loop is a continuous event pattern for stage elements that will move or transform before eventually returning to their initial state. Loops are often very simple in execution. A loop should not be mistaken for a cycle, although a loop may be an aspect of a cycle.
Some loops have virtually zero impact on gameplay, such as changing backgrounds, while some feature global shifts as on Rainbow Cruise - the game state will begin on the cruise ship, which will eventually drop below the lower blast line as the players make their way around obstacles, eventually circling around the stage where a new cruise ship will be waiting for them to begin the loop again.
Loops are frequently an aspect of rails.
Examples of loops
Cycles consist of a loop of regularly occurring, noncontinuous individual events.
Examples of cycles
A rail is any stage element that follows a set path to completion and may or not form a loop. The term "rail" is derived from a type of Shoot 'em up video game subgenre which requires the player to follow a specific route from which they may not deviate, as in Star Fox 64. Incidentally, several stages from the Star Fox franchise feature rails.
Examples of rails that loop
Examples of rails that do not loop
Random events occur outside of prediction, although they are sometimes dictated to occur every so often by default so as to actually appear in the game.
Examples of Random events