Jigglypuff retaining its Puff Up-induced size, the most well-known version of the glitch.
The Regenerating terrain glitch or Interrupted Final Smash Glitch is a glitch that causes certain Final Smashes to stay in their activated state if the character is inside a piece of terrain that has just regenerated.
Bridge of Eldin - The middle section of the bridge. The easiest and most popular way of getting the glitch to occur.
Pirate Ship - The King of Red Lions' appearance. This version of the glitch is the most difficult to perform, as the terrain in question is offscreen. Also when the Pirate ship comes in contact with the rock island.
Puff Up glitch - Occurs when Jigglypuff is in the middle of using Puff Up, causing it to keep its increased size. Being swallowed by Egg Lay increases its size even further. One of the most common Final Smash glitches.
Diffusion Beam glitch - Occurs when R.O.B. is in the middle of using Diffusion Beam, causing the move to last indefinitely. The move sometimes gets stuck in one of its modes; charging a Gyro often fixes this. However, if the platforms reseal before the beam is released, R.O.B. will not fire anything at all.
Golden glitch - Occurs when Fox, Falco, Wolf, Kirby, or Marth are in the middle of their respective Final Smashes (Landmaster, Cook Kirby, and Critical Hit). Causes the Final Smash aura to become stuck in its "on" state; the character will be able to act as normal until KO'd, they can use their neutral special move, the camera may remain zoomed in and time may remain slowed (if the glitch happens during these effects), and no more Smash Balls will appear.
Invincible glitch - Occurs when Meta Knight uses Galaxia Darkness on any character. Causes the opponent caught in the Final Smash to become invincible, but frozen in place.
When performing the Puff Up variation of the glitch, any battering, shooting or status item picked up by Jigglypuff will also become giant. The effect wears off when the item is thrown, however Wario's Bike, Snake's Hand Grenades and Cardboard Box, and Link's Bombs will retain their altered size.
Jigglypuff's optimal moment of activation of Puff-Up (for largest size increase) on the Bridge of Eldin is almost the exact moment the bridge begins to repair itself--that is, the moment the black portal "static" forms the framework of the middle section. As Jigglypuff's size can also be affected by Giant Mushrooms, Giant Brawls and Egg Lay, layering all methods properly makes it possible for a Jigglypuff character model to become so large that only perhaps a quarter of it can be seen in normal matches at one time (except when crouching, which brings into view more of Jigglypuff, if only because crouching slightly squishes its model). In fact, ducking will cause its face to take up nearly all of, if not the entire screen.