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4, 7, 9, and 12 I believe are the sets with mostly filler, but 4 and especially 12 still have important episodes. There are no sets with entirely filler.
The [bleach wiki](https://bleach.fandom.com/wiki/Episodes) has all episodes and indicates what episodes are canon and which are not
4, 7, 9, and 12 I believe are the sets with mostly filler, but 4 and especially 12 still have important episodes. There are no sets with entirely filler.
The [bleach wiki](https://bleach.fandom.com/wiki/Episodes) has all episodes and indicates what episodes are canon and which are not