the phantom prize

In the past i discovered this shit on my own, and it was quite unpleasant...
Reading ZED ff6 bug list gamefaq i finally found some documented detailed about it:
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SrBehemoth rips you off -

Both the living SrBehemoth and the undead SrBehemoth give up Behemothsuits as
win items. While that sounds good, most veterans will recall that the prize
for the duel SrBehemoths battle in the Cave in the Veldt is actually one
BehemothSuit and one ThunderBlade, or in very rare cases, perhaps a Jewel Ring
instead of the blade. The monster stats guide and the ROM itself both claim
the former about both monsters giving up BehemothSuits, so now the question is
why so many people claim the latter is true. That, unfortunately, is because
it is true, due to a bug that occurs as a result of the formation switch that
brings in the undead SrBehemoth. The two monsters are not only in seperate
formations, but also in seperate slots; the living monster in slot 1, undead in
slot 2. What was supposed to happen was that by not having the monsters in the
same spot, the win data from the living SrBehemoth would be carried over to the
new formation containing the undead version, resulting in your getting 2
BehemothSuits. What happens instead is that when the battle ends and the game
goes to check for win items, it reads the first formation slot for the monster
number needed to retrive win item data, and gets FFFFh, the number that says
there's no monster in the slot. Since the game did save the data that says you
defeated the monster in the first slot, it will try to retrive the win data
anyway, and ends up going to offset 1031FE, where the common win item is listed
as a ThunderBlade and the rare item a Jewel Ring in FF3us. Keep in mind that
in FF6j and the PS versions, these are not the same.
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now, i searched in the whole monster list and no one drops jewel ring as rare and thunderblade as common
I also searched for some info about 1031FE address, but i cannot find any clue about what's that area and from where i should edit it, making it become a really common or empty prize, instead of the thunderblade and the ring.
Anyone knows something more about it?

Are you sure that it's not just reading garbage data from somewhere? If you change it you might be breaking something else...

I really know what i did it here, and just today i discovered that it's also a listed and known bug... so no garbage here.
Besides, in the case you'll record my current task, you'll see that the boss drops thunder blade or jewel ring(they're not his drops!), so i'm 110% sure about that.

Edit: oh, i got what you meant! if that's garbage, then i wanna know what's this garbage and if i can manipulate without breaking anything, especially because CotG might be full of those situations and i don't wanna be forced to take in consideration what are those 2 items in my hack and possibly avoid to increase further the size of the AI of my monsters, just to be sure to avoid the death of mosters that won't be in the same slot of a changed formation...