A plot in an Anime that was not in the Manga is referred to as “filler.” These are produced as a result of the fact that anime production occasionally outpaces manga output. Fillers don’t add to the tale and are usually of lower visual and narrative quality.
The “single upgrade filler,” on the other hand, is a type of filler. This takes advantage of a filler episode to introduce a new power, technology, costumes, secondary characters, and so on without having to incorporate it into the main plot.
Outside of “anything got an upgrade,” the episode can be ignored in these circumstances. Fandom also uses the term “filler” to refer to anything that isn’t in the original material. This arises from the practice of adaptations that are on the verge of catching up to the source material padding things out with original story arcs, episodes, and general substance.
This trope is not the same as Overtook the Manga or Adaptation Expansion, but such occurrences are frequently associated with it.
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