Male
Seen 1 Day Ago
Posted June 12th, 2019
120 posts
3.5 Years
That wouldn't help me, that would just change the 16th byte of the item. It wouldn't change any pointers since the held item effect is determined by the 16th byte and not an actual pointer to a routine. There's probably a table somewhere that points to all of the held item routines, and the 16th byte of each held item determines which pointer to use from the table.
The hold effect ID is an arbitrary number. There is no table. For example, for thick club, In the damage calc routine it loads the attacker's hold item effect ID, compares it to thick club, then checks the species ID to determine whether or not to boost the attack.

If you wanted to raise fairy type attacks, you would need a function hooked into an appropriate place to check if the current move type is fairy, check if the attacker is holding an item with some unused hold item effect, then raise the attack if all of these checks were true.