First off, no I'm not going to make an FE8 version. Now then
For those who don't know, an arms scroll is an item from Path of Radiance that increases the weapon level of the currently equipped weapon by one full letter eg: C raises to B, E raises to D etc. I think it's been a pipedream of some hackers for a while to have a functioning arms scroll for the fegba games (FE7 especially)
Well here it is guys
A word of warning, to get this to work properly you're going to have to be familiar with at least hex editing and nightmare. If you aren't comfortable with either of those I suggest reading Blazer's Ultimate Tutorial, it should help teach you what you need to know. Now on to the steps:
Step 1: Repoint your tables
In the vanilla FE7 ROM, there are multiple tables for items but the ones you need to focus on are the item conditions, effects and stat boosting text tables.
Blazer's topic here has a lot of the info you need about the table locations and how to repoint them and about making new items in general.
I highly recommend using his patch that repoints all the tables for you but I'll leave that to your discretion
Step 2: Inserting the hack
The Arms Scroll hack has three parts: the condition, which makes the item usable or unusable based on certain conditions; the effect, which is the actual code that makes things happen; and finally the text code which loads the "Weapon Level increased" popup when the item is used(basically the exact same prompt used get from using a stat boosting item) Here I'll paste the raw hex to each part, your job is to put them in free space and make a note of where you put each one.
1E B4 01 20 0F 4C 10 4B D9 7A 48 22 4A 43 0F 4B 9B 18 1E 21 5A 18 12 78 D1 00 8A 18 92 00 0C 49 09 68 51 18 07 31 09 78 07 29 07 DC 28 22 51 18 59 18 09 78 00 29 01 D0 FB 29 00 DB 02 3C A6 46 1E BC 70 47 47 6F 02 08 F0 A3 03 02 08 BD 02 02 60 60 01 08
07 B4 15 48 48 21 41 5C CA 00 8A 18 92 00 13 49 09 68 51 18 07 31 09 78 28 22 89 18 C0 7A 48 22 42 43 0F 48 80 18 40 18 01 78 1F 29 07 DB 47 29 07 DB 79 29 07 DB B5 29 07 DB FB 21 06 E0 1F 21 04 E0 47 21 02 E0 79 21 00 E0 B5 21 01 70 05 4A 96 46 07 BC 70 47 00 00 F0 A3 03 02 60 60 01 08 08 BD 02 02 0F D2 02 08
01 4D 02 48 00 47 00 00 50 07 00 00 55 CE 02 08
Step 3: Assigning Pointers to the Hacks
Now that the hacks are all inserted, they have to be pointed to in the tables. The formula for the offset to change is (ItemID * 4) + baseOffset = desired offset
eg; if the table is at 0xD00000 and I want to edit Vulnerary's(0x6B) entry, we get; (0x6B * 4) + 0xD00000= 0x1AC + 0xD00000= 0xD001AC. Again, Blazer's topic has more info if you need more help. From here you put in pointers to the pasted piecemeal hacks in the slot for the item you want in the corresponding tables so a pointer to the condition in the condition table etc. Pointers are little endian meaning they're bit reversed with the 0x8000000 bit set
Step 4: Finishing touches
If you've reached this step then the arms scroll should be technically functional but it's not done yet. In your item editor module you need to edit 2 things; the stat boost pointer and the item/staff use. The stat boost pointer can't be left as 0x00 of else you'll experience bad glitches with random stat increases so you instead need to make it point to an actual array of 0's. You need at least 9 consecutive zeroes for it to not break but I'd have more just to be save. Lastly, you need to set the item use to a stat boosting item, any will do fine so long as it is a stat boosting effect.
Step 5: Profit
The arms scroll has been successfully inserted! The only things left to do are change the item name, description etc and insert an icon if you want. Otherwise you're finished. Congratulations on your new Arms Scroll.
A few brief points before you all rush off to do your thing:
1: The scroll works on all weapons and staves but not dance rings or dragonstones
2: The scroll determines what weapon level to change based on the item IN THE FIRST SLOT. Unfortunately, I couldn't make it read the "equipped weapon" so you'll have to live with it affecting the first item. It shouldn't be that big a deal I just wanted to make sure you understood first
3: The conditions for using the item are as follows: the item will only work if the weapon level of the type of the item in slot one is between E and A and if the first item is a weapon or staff; if it's S or null it won't be usable and if there's an item or no item in the inventory
4: Currently there is no check to prevent multiple S ranks. If there's demand for that to be changed, I can add it in later.
Thank you for your time and enjoy