I am looking to change which items are carried in marts. Particularly, I am trying to add evolution stones. How do I go about that?
Just found this myself, if HG SS has a decomp that is, if there's a complete decompilation of the source code(most likely on github), you can find a listing of all the items in the game by their codes, that's what I used in firered. the file for items should be items.h
If it's like the one I have, the item codes will be in decimal, so you'll need to convert it to hexadecimal before you can insert into the game.
Then the last step is just to use the map editor for your gen to pull up the script for the vendor in question, go to the bottom where it defines the items in that mart.
should say something like
'-----------
' MartItems
'-----------
#org 0x16ACD8
#raw word 0x4
#raw word 0x16
those raw words are the items.
add the items you want before the last listing which should say
#raw word 0x0
compile save and you're done.
So far I haven't found anything limiting how many items a vendor can sell, I added 4 or 5 without issue.
Each item already has a default price. How to change that I don't know.