1 - If Monster #3 Item (rare) has been stolen
- Set normal attack look --> unarmed (if it's a weapon)
- Set att. power
- Set defense (if it's a piece of armor), etc.
To reflect the loss of the item
So FC XX YY ZZ, XX is the number of the command, obviously. YY is the item stolen, 0 for common, anything else for rare. ZZ are the targets.
2 - If formation pack zoning is 54 then
- Set Monster #4, #6 level to 22
- Set Monster #4, #6 hidden status: Safe etc.
In order to reflect that certains areas have certains effects on monsters, eg. near Kefka's Tower, monsters are more powerful and use stronger magic or monsters sometimes attack themselves when they are near the Magic Tower (because the power of the tower makes you become crazy)...
3 - If current background is Grass Wob then
Can be used by "geomancers" enemies (like evil moogles).
4 - If Terra has command Summon available then
5 - If monster #5 is controlled then
6 - If esper Bahamut has been gotten then
7 - If game time hour is 58 then
8 - If 2 players are playing then
9 - If party contains 3 characters then
10 - If battle is in back
row attack then

11 - If ally #1 ATB is full then
12 - If allies are all in "ready" stance (everybody selected a command and is waiting to attack) then
13 - If Edgar is using Def Command then
14 - If ally #2, #4 is/are trying to run away then
15 - If Relm has Cat Hood equipped then
16 - If Gogo is in the sky, waiting to jump then
That's all I can think of! I think everything can fit into 3 or 4 bytes. Oh, and hi everybody by the way!
And, it's not an FC command but, may you please have Undead protected from Death has immunity against Phoenix Down, Elixir and Revivify?