Some final code requests (and screenshots)

Well in that case, use a debugger and set a breakpoint at C2/566E to see if the code is executed when you use step mine.

To be clear, this code is run at the start of a battle, not when you use step mine.

The reason it didn't work is because you're using a 1.1 ROM, and I gave you the code for 1.0. Searching the 1.1 ROM for "E0 44 00 D0 09", the code I quoted  appears to start at C2/586E in 1.1.

Ahh, you are correct about the code being run at the start of the battle.  I actually did modify the correct code, because I simply searched for the code you gave me rather than look for the address (I prefer doing it that way unless I can't find it in a search).

The really strange thing here is that the MP usage for Step Mine is correct in-battle (54), but when I go through the menu and look at Step mine, it still says 108...  This is why I was confused, and I don't know why the MP usage of Step Mine in the menu is not updating!