Oh man, I finally figured it out!
FF6 doesn't have "second forms" like the other Final Fantasy games do so I was thinking at first in using something like:
Spell: Fire
End first wave of attack
If monster has attacked by element: Fire
Monsters #4, if hidden/dead, brought in with their HP restored, suddenly
Lore: Pep up
End
This would basically make it so that if you cast any spell with the Fire element attribute, the monster would come in, and the monster affected by the element Fire would kill him self with the spell Pep up leaving only the last monster.
Although .. I've found a better solution!
At the last battle with Kefka, theirs a series of battles you do.
You fight the bottom, middle, top and then Kefka.
All four are classified as battles, now get this.
If you open up FF3usME and look at battle #282, it's like a script inside a script! It's fucking ingenious! (You don't fight form #282, that's why it's ingenious
)
This is #282:
If VAR036 has all the following bit cleared: 0
Target self becomes untagetable
VAR036 set bit: 0
End if and reset targeting
If monster is in formation #471
if 1 monster(s) or less remain
Call form. #512 (Hit, Tiger, Tools, Magic), gets max HP
End if and reset targeting
If monster is in formation #512
If 1 monster(s) or less remain
Call form. #513 (Girl, Sleep), get's max HP
End if and reset targeting
If monster is in ... etc
Basically, once you defeat the Bottom (Form 512), you move to the next battle.
I was originally really nervous about how many bytes I could use on the boss section of my rom hack and also rather nervious about the molds.
I mean, I don't believe you can have two large sprites in one battle, the battle won't support the mold sizes. :/
So I found a better way around!
I'll make two battles and mimic what square did with the Kefka battle.
Although, I'd want it to be instantaneous instead of moving up the screen to the next battle.
I'd kind of like the battles to overlap each other but I'm not sure how to do that yet so I'm kind of pending on whether or not I should use this new method or stick with my "Pep Up" method. :/