Lovely, though I hope you can cram all of it into one ExGFX file. The head and bottom of the flower platform are mostly the same tile, so I can't see it being too difficult.
hmmm... I quite don't get how the flower have any duplicated tiles, and i don't think it is at all possible to put all of it in a single ExGFX file, possible 3, but 1 is impossible.
I don't know a thing about ASM, but a sprite can't use more then 1 exgfx file? if that's the case i can put the Dryad, and the attacks in different bins.
Three ExGFX files for a boss is pretty extreme, and with ROM space as tight as it is, I fear we'll end up overflowing. See what you can do about working it into two, but anything more than that will be too excessive. It looks like frames 2 and 4 in the first box are the same, and the flower's bottom is the same in every frame until it gets thorns. The fruit at the bottom can probably use a few less frames as well.
As a whole, if you're able to "reuse" a couple of frames and cut one or two, I think we can make this fit in two.
Regarding the size of the files individually; there can be 4 sprite files. The first one is primarily reserved for Mario's 8x8 tiles for running, etc, as well as the actual "frame" for Mario himself, Yoshi/podoboo, and other "dynamic" things. Usage of this page is usually not recommended unless the circumstance is extreme enough to warrant it. The second is primarily for powerups and a few global enemies. The third and fourth are for whatever the purpose requires, but are used for tileset-specific enemies, bosses, and the like in SMW originally.
If possible though, 3 graphics files would be ideal to use (although 2 graphics files would be even more so), since I doubt dynamic sprites are going to be used in this project due to space limitations.
i'll try to make it fit in two bins then. Thanks for the explanation Sonikku.
EDIT: It was hard, but i got this:
Removed an body frame (just making it go up and down will have the same effect) and a Purple berry frame. Then i managed to make them all fit the 2 ExGFX files but the brambles. so i needed to cut it in several 8x8 parts. Is there any problem with it?
No, blank tiles do as far as I know take up the same amount of space as used tiles , I meant it more like filling unused tiles up with other ExGFX' stuff to combine some ExGFX files, but yeah it wouldn't help a lot.
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No, blank tiles do as far as I know take up the same amount of space as used tiles 
Citation not given.
All ExGFX files are compressed prior to insertion, and repeated data (for example the 00 00 00 00 that make up a blank tile) compresses better than random data.
All (useful) compression formats work like that: Predictable data shrinks, unpredictable data sees no (notable) change.
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