Guide to freeing up more enemy slots

This is a rundown of enemies in the game that are superfluous and redundant; some cinematic enemies can be merged with instructions based on formation to call different scenes, and some normal enemies are only encountered in one or two places and could be replaced with other enemies without effecting gameplay balance much.

I'll explain who can be replaced, and what formations to change appropriately, so you can free up more empty slots for adding new enemies.

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#374 Cadet - The Cadet only appears in one battle at the Imperial Camp during the sequence where Cyan attacks. It can be replaced with #2 Templar, which has an identical appearance, also appears at the Imperial Camp, and has identical stats save for slightly lower HP, which is barely an issue in this circumstance. The Cadet appears in formations 59 and 503 (though the latter seems unused), replace it with the Templar in these formations and the Cadet is effectively dummied.

#335 Grunt - The same situation as the Cadet, the Grunt only appears during the scripted Cyan attack on the Imperial Camp. It can be replaced with #1 Soldier who is identical in almost every way, just some very minor stat differences that mean nothing. The Grunt appears in formations 59, 60, and 62, replace it with the Soldier and the Grunt is dummied.

#26 Doberman - The Doberman appears in the Imperial Camp as the guard dog fought when you try to open the locked chest. Given it is such a minor enemy, and largely identical to #133 Vector Pup, the Doberman can be replaced with the Vector Pup without much impact, the chest fight will just be a bit easier since the Doberman has more HP than the Vector Pup. The Doberman appears in formations 46, 48, and 62. Note however that the Doberman appears on the Veldt as a Rage, so whichever enemy you add in its place, you may want to also make sure it appears on the Veldt. 

Alternatively, you could "swap" the Doberman with one of the 256+ enemies that appear as normal encounters but do not have a Rage; the simplest is #357 ProtoArmor, as that enemy already appears on the Veldt but just doesn't have a Rage. It appears in formations 402, 403, 404, and 417. You can substitute other enemies above 256 as well like #258 Mega Armor, #261 Prometheus, #280 Nerapa, and #361 Naughty. The issue there is that these enemies normally do not appear on the Veldt, so if you want them to be usable as Rages, you'll need to edit packs as well as formations, which I won't get into.

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#276/277 Tritotch - These are the two cinematic enemies for the intro of the game and after the siege of Narshe, respectively. Thus they have no AI script but to trigger the scene, and a formation check can be used for this. Formations 447 and 448 are used for them, respectively. Insert commands in their AI script to check their formation and cue either scene appropriately, as shown below, and the other Tritoch is unnecessary and can be repurposed.



#362, 363, 364, 365 Phunbaba - These four versions of Humbaba are for the fight with Terra alone, the first fight with the party, the second fight with the party, and the final fight where Terra joins you. While it's possible all four could be merged, I think it is safer, simpler, and and creatively preferable to keep the first and second visits separate (in case you want to make him stronger on the rematch, for instance). As with Tritoch, use formation check commands to give Phunbaba Invincibility in the first fight, and to trigger Baba Breath in the second fight. While the cinematic Phunbaba has higher stats than the normal one to kill Terra faster, this is a moot point, he's invincible and she's unequipped.



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For additional convenience, here's a rundown of other unused enemies, as well as enemies unnamed in usME (thanks to FF6 Tools for some help with this)

#271 Umaro - unused fight seemingly intended for the WoB
#282 "Kefka" - seemingly intended for an earlier version of the final battle where an invisible enemy would call in the next tier. I erased this script and the final battle went as normal, so I can confirm this enemy is unused.
#310 Colossus - unused boss seemingly intended for Sabin's scenario
#311 CzarDragon - we know all about him

#366 Unnamed - used for Terra's AI in her flashback at the start of the game
#367 Unnamed - Apparently this is for the battles with Kefka at the Imperial Camp. However, I removed this enemy from the formations (formation 504, pack 311/$38) and the battle proceeded normally without any noticeable changes. This enemy may not be necessary, but I cannot be 100% certain.
#368 Unnamed - used for AI Cyan in the Imperial Camp
#370 Unnamed - used for Gau when he appears on the Veldt
#371 Unnamed - used for the Leo vs Kefka fight
#372 Unnamed - used for battles with Kefka at the Sealed Gate.
#375 Unnamed - Seemingly unused. The enemy is used in formation 508, but 508 is not included in any packs I can see. 508 is flagged as the "Espers & airship" event, but removing the enemy from the formation did not affect the scene. Therefore, I believe this enemy is unused.
#376 Unnamed - Seemingly unused. The enemy is used in formation 509, pack 317/$3E, and the formation is flagged as the "Kefka vs Esper" event, but pack $3E is never called up anywhere I could find and removing the enemy from the formation did not effect the scene in Thamasa. I recall reading somewhere there was signs of two cinematic fights between Kefka and an Esper, so this seems to be a leftover of the scrapped one.
#377 Unnamed - The enemy troopers Terra fights in her flashback, they have a blank AI script so they don't attack her. You can merge them with the normal imperial enemies by setting those enemies to inflict Stop on themselves if they're in formation 485 (the one used in the flashback).
#378 Ifreet - The red Ifrit palette swap Kefka fights in Thamasa, of course
#379 Unnamed - This enemy is basically a catch-all for most of the battle cinematics in the end of the World of Ruin - the two scenes with Kefka at the Sealed Gate, the Espers attacking the airship, the Espers emerging from the Sealed Gate, and Kefka killing Gestahl. The script also includes a flag for formation 390, pack 362/$6A, but it isn't called up that I can find. The formation once again has the "Espers & airship" event flag, but removing this enemy from that event did not change that scene. Maybe the flag itself is dummied?
#380, 382- Unused and dummied

Note that #383 is also unused and empty, but is a null entry for "empty" enemy slots, don't use it.

Finally, there are some unnamed Guard enemies that I'm not sure what they're used for. I'd appreciate if anyone can let me know what they're for so I can clarify if they're unused and mark them as dummied enemies. The numbers are 368, 375, 376, 380, 382, and 383. They all have just normal attacks in their AI scripts except for 368, which has a two-turn script that includes a chance to use Joker Death, curious indeed. I've no doubt that one of these is used for Shadow but I'm not sure which one, and am not about the others.

see http://masterzed.cavesofnarshe.com/GameDocs/monster.txt

Unfortunately that just mentions what one of them does, 368 for Cyan's AI time. The rest it doesn't mention.

Merge #377 Soldier with #1 Soldier - This is one I will definitely have to test. The #377 Soldier is the enemy used in Terra's flashback where she fries the Imperial troopers, it has only 1 HP and no AI script. All the event data for this scripted fight is tied to the enemy used for Terra's script, so I believe the Soldiers can be swapped without harming anything, and the event will be fine. The normal Soldier only has 100 HP, so Terra will still certainly kill the trooper in the scene.

I made a modification to the Terra flashback scene in my project and ran into some issues with swapping out #377 for a similar enemy.  #377's battle script is completely empty so it does not fight back, while #1's battle script has an Attack command in it.  Therefore, if I put a different enemy in #377's place that did not have an empty battle script I was finding that it was often able to take a turn and attack Terra before she got the chance to kill it.  It can't kill Terra, but it still breaks the flow of the scripted flashback if the enemy actually takes a turn.

Unfortunately that just mentions what one of them does, 368 for Cyan's AI time. The rest it doesn't mention.

it does identify the final 2 as unused.

also, i believe that #383 is a Null indicator for enemies in formations, so you'd never want to try putting a valid monster in that slot.

Merge #377 Soldier with #1 Soldier - This is one I will definitely have to test. The #377 Soldier is the enemy used in Terra's flashback where she fries the Imperial troopers, it has only 1 HP and no AI script. All the event data for this scripted fight is tied to the enemy used for Terra's script, so I believe the Soldiers can be swapped without harming anything, and the event will be fine. The normal Soldier only has 100 HP, so Terra will still certainly kill the trooper in the scene.

I made a modification to the Terra flashback scene in my project and ran into some issues with swapping out #377 for a similar enemy.  #377's battle script is completely empty so it does not fight back, while #1's battle script has an Attack command in it.  Therefore, if I put a different enemy in #377's place that did not have an empty battle script I was finding that it was often able to take a turn and attack Terra before she got the chance to kill it.  It can't kill Terra, but it still breaks the flow of the scripted flashback if the enemy actually takes a turn.

Noted, thank you. I wonder if perhaps speed could help with that, like making Terra really fast with Auto-Haste to ensure she acts first.

EDIT - Nope. Hm. Yeah may have to give up that one sadly.

EDIT x2 - Success! And probably the secret to other mergers too - the "If enemy is in formation" script. I added a script to the normal Soldier that if they're in Formation #485 (the Terra cinematic battle), they give themselves Stop status. Ran through that scene a dozen times, they never attacked, and ran through the Imperial Camp where the Soldiers have also been added and they attacked fine.

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A question - does anyone know if Formation 496 is used for anything special? It's the Soldier from Terra's flashback scene, but just one of him.

In good news, the Cadet and Grunt were replaced no problem, just a matter of changing them in enemy formations. And I merged the Soldier from Terra's flashback into the normal Soldier as described above. I also merged the three versions of Tritoch and the two versions of the Guardian - their AI script checks the formation to determine what happens. The Guardian I had to take a liberty with though, because it needs the "can't run" flag for when it is faced in Kefka's Tower. Since the party cannot run from it anymore in other encounters where it is invincible, it now Sneezes the party away one by one.

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The Doberman has been replaced with the Vector Pup in the Imperial Camp, and the Doberman itself has swapped slots with the Mega Armor, turning the Doberman into a Dummied enemy and the Mega Armor is now a Rage. And as proof, here it is on the Veldt and in the Rage menu - the two packs that had the Mega Armor were changed with the Doberman's accordingly, causing Mega Armor to appear on the Veldt when you encounter it in the Imperial Base or the Palace.

Okay, have tested and double-checked stuff, I think it's good, so a download link will be added to the OP with a Read Me attached.

In this released version of the mod, there are 7 new enemy slots emptied, and as part of this the Mega Armor is now a Rage for Gau, its special ability is Missile.

I didn't replace the Hidonites because that's so easy anyone could do it in usME, no one needs a patch or tutorial to do that. I could not merge Siegfried or Chupon because they need to be available to fight in the Coliseum, and I could merge the "boss" versions into those versions but again, that is easy for people who wanna do it. I'm good with this for now, releasing it.

The patch is for a 1.1 unheadered, unexpanded Rom. But if you have an expanded rom and wanna make use of these merging techniques, the Read Me file in the download is comprehensive on what was merged and how, so you can reference the Read Me and the new AI scripts and do it yourself, it isn't overly complicated with the steps explained.

Additionally I've had an idea making this that will take more time to look into and be a much bigger project, but I'll cover that in a separate thread in the future when I have something to show.

OP updated for clarity. I removed the patch download to avoid it causing any problems, easier to explain how to merge enemies anyway. Also included a list of the unnamed enemies used for cinematics and such, some of which are also unused but isn't immediately obvious without testing.