A Generator is a gameplay mechanic in the Subspace Emissary. Subspace Generators appear as dark purple portals about the size of Bowser. Their function is to produce enemies until it is destroyed. Each one generates only one type of enemy. There is a set limit on the number of enemies on the screen at any given time, so if the player gets rid of one, it simply spawns another. However, the limit to how many enemies it can spawn is thirty, and if the player can defeat them all, the Generator will simply stop spawning the enemy, but it will not disappear. Most commonly the Generator will create Mites or Bytans, but later in the game Floows, Primids, and even Fire or Metal Primids will be produced.
Unlike every other enemy in the game (including Jyks), there is no health bar display for a Subspace Generator. Because of this, there's no way to know how much of a beating it can take. This is mainly because they are treated as stage elements, not enemies.
In Super Smash Bros. for 3DS
Generators make a return in Super Smash Bros. for 3DS, appearing as enemies in Smash Run. They spawn mites, but can uncommonly spawn other enemies, similar to Bullet Bill Cannons.
This mysterious, formless entity appears only as a strange spiral in the air, spitting out enemies--mostly mites--and making life difficult for any fighters unlucky enough to deal with them! The faster you defeat them, the more stat boosts they're likely to drop, so hurry up!