Best help you're going to get:
1) MetEdit is a level editor for Metroid. Very easy to use. If I remember correct, it also had the problem of making all moved items retrievable over and over again . . . If this is the case, someone should know of the fix (I saw one hack that didn't have this problem).
2) Tiles for enemies are not compressed, so they can be changed quite easily in a program like TileLayerPro . . . Scenery *may* be compressed (which would make it impossible to do unless someone's feeling really generous). Then again, it may *not* be compressed too. Can't remember.
3)
I will be willing to help in finding things such as HP values, palettes, etc.... (ie- you do the hack, but I'd find stuff you can add in).
Hmmm... I wonder how easy it would be to make a version of SABS for Metroid? Fewer enemies.
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