some questions

[polytope]

- Davaeorn's Horrors are no longer beside him, making this battle about 50% easier. He also seems to love casting fireballs onto ground, without any target nearby.

Is it possible, in theory at least, that the "casting fireballs onto ground" means he's targeting the invisible creature (bird or something) which gets created in the web/stinking cloud so enemies walk away from it? I did notice he constantly blasted fireballs near-middle point of where his trigger with web/cloud landed. He did target Cone of Cold correctly, while Sunfire has no targeting whatsoever. That's all I can say since I killed him prior to his low-level castings.

 

This is actually an engine level scripting bug introduced by BG:EE. From what I hear, just one of a bundle of a bugs (I'm not planning to buy EE).

[DavidW]

- Davaeorn's Horrors are no longer beside him, making this battle about 50% easier. He also seems to love casting fireballs onto ground, without any target nearby.

Is it possible, in theory at least, that the "casting fireballs onto ground" means he's targeting the invisible creature (bird or something) which gets created in the web/stinking cloud so enemies walk away from it? I did notice he constantly blasted fireballs near-middle point of where his trigger with web/cloud landed. He did target Cone of Cold correctly, while Sunfire has no targeting whatsoever. That's all I can say since I killed him prior to his low-level castings.

 

This is actually an engine level scripting bug introduced by BG:EE. From what I hear, just one of a bundle of a bugs (I'm not planning to buy EE).

 

I don't think that's right here - Davaeorn does have specific scripting to cast at that point in certain circumstances. His intended strategy is to make the central junction full of webs, then teleport around it and fireball / lightning bolt people caught. That includes a certain willingness to fireball the junction on spec even if he doesn't have LOS to someone, in case they''really round the corner.

 

This is actually one of the oldest bits of scripting in SCS and it's more "programmed" than most of my AI, with the attendant advantages and disadvantages - more variety and interest, more risk of looking brittle in unanticipated circumstances. In v28 I've tightened the conditions a bit but I'm reluctant to lose it entirely.

[polytope]

Looks like I spoke too soon, it's been a long while since I played BG1 with SCS...

 

Although the other thing kreso mentioned - spiders shooting webs in midair - sounds like a genuine example of this EE bug. It might happen only with ForceSpell() or similar which explains why spiders and gauths would both be affected.

[DavidW]

Looks like I spoke too soon, it's been a long while since I played BG1 with SCS...

 

Although the other thing kreso mentioned - spiders shooting webs in midair - sounds like a genuine example of this EE bug. It might happen only with ForceSpell() or similar which explains why spiders and gauths would both be affected.

 

Looks like. (I've never seen anything like it reported on non-EE installs, which is usually a tell.)

 

I should say that I have a lot of sympathy for EE here, because it's basically a larger-scale version of SCS itself over the last year. I believe the updated-and-unified SCS is in the longer term a much more solid and stable base for the mod - but even now at version 28, I'm only beginning to think that it's as bug-free as the SCSv21/SCSIIv21 combination. My experience of EE is similar - the EE engine (whose development I have had nothing whatever to do with, I should say!) is in most respects a much more solid basis for using and modding the game, but unsurprisingly as a newer product it has some relatively-visible bugs of the kind that will have been caught in BG2's long-ago development cycle.

[kreso]

This is actually an engine level scripting bug introduced by BG:EE. From what I hear, just one of a bundle of a bugs (I'm not planning to buy EE).

The post you linked describes what spiders do, and it does seem to be EE specific. It happens on approx 5% on fired webs.

As for EE and if it's worth the price, and totally off-topic.....well, first time I saw it was almost immediately upon release - buggy, slow, laggy etc. I got it after the latest patch (BG1) and on my old laptop with Intel Graphics it runs faster than BG2. It looks much better, more fluid. Quick save is instant (not quick!), load times 6x faster. No lag even in battles with a multitude of explosions, creatures, spells.

I think EE 1 is well worth it, at least with SCS AI (I never played "naked" EE, so can't comment on AI implementation).

EE 2 I didn't play much. What bothers me, and I think other veterans will have the same issue - the game feels very "modded" even without mods. New areas really stand out as "new". NPC vampire was already seen, several times...and I dislike all vampire mods. Just because it's implemented in game doesn't make it any better. Even if I never had played the old BG2, I could tell which NPC is "new" and which are "old".

Also, there's very few "enhancements" in spells, HLA's, kits, items, which I was hoping for the most. It makes me sad when a Beastmaster still summons a Fairy Dragon, after a dozen years...still he has his familiar dragon.

NPC quests are nothing to write about, and I must say that I've played mods which had better dialogues/ideas than these.

EE 2 needs much, much work.

The best part is the engine that runs the game, but if mods weren't released/planned for EE games, I'd never consider any of them. Now, with SCS, RR, aTweaks, soon to be Revision mods - I have my base setup and I can see it only getting better from there. I have higher expectations from modders than developers.

[polytope]

I got it after the latest patch (BG1) and on my old laptop with Intel Graphics it runs faster than BG2. It looks much better, more fluid. Quick save is instant (not quick!), load times 6x faster. No lag even in battles with a multitude of explosions, creatures, spells.

Faster operating speed for a game more than a decade old would be good, but not at the cost of new and game breaking bugs.

 

EE 2 I didn't play much. What bothers me, and I think other veterans will have the same issue - the game feels very "modded" even without mods. New areas really stand out as "new". NPC vampire was already seen, several times...and I dislike all vampire mods. Just because it's implemented in game doesn't make it any better. Even if I never had played the old BG2, I could tell which NPC is "new" and which are "old".

Yeah, the artwork for the new areas doesn't look high quality - not for a commercial product.

 

Also, there's very few "enhancements" in spells, HLA's, kits, items, which I was hoping for the most. It makes me sad when a Beastmaster still summons a Fairy Dragon, after a dozen years...still he has his familiar dragon.

Ludicrously, a Dwarven Defender can apparently select hardiness as a HLA, which stacks with his natural barbarian-esque resistances and 50% more from his "defensive stance" to give him 110% resistance to all physical damage.

 

Oh sure, hardiness stacks with itself in vanilla ToB, but we all know that was a rushed job with only 6 months work on the entire expansion and hardly any playtesting of the poorly balanced HLA's. What's the EE team's excuse?

 

OT, but it's funny that any discussion anywhere of which BG2 classes and kits are the "best" revolves around the silly HLA's which shouldn't exist (and the bugged ranger/cleric, another developer oversight that wasn't fixed for EE...). My favourite example (besides hardiness stacking with itself) is blades getting Improved Bard song as HLA inspite of their supposed kit disadvantage being a song that doesn't improve with levels.

[kreso]

Faster operating speed for a game more than a decade old would be good, but not at the cost of new and game breaking bugs.

One thing that bothers me above all bugs (which will be fixed) is "integrated Fixpack", making Boots of Speed hyperpowered and Ironskins crappy (1 round casting speed is outright crazy. I hope they at least flagged it as "combat protection", otherwise people playing without SCS will be removing it with Ruby Rays.) , amongst other things such as making weapons overenhanced (I really don't think +1/+3 vs x translates into a +3 weapon). So before I start adding mods, I need to manually edit every little thing I don't like, and then start installing, to make sure SCS uses changed spells/items as well.

 

Ludicrously, a Dwarven Defender can apparently select hardiness as a HLA, which stacks with his natural barbarian-esque resistances and 50% more from his "defensive stance" to give him 110% resistance to all physical damage.

They probably forgot about Hardiness via Wish as well, so getting 127% shouldn't be a problem. Defender of Easthaven is readilly available as well, so who cares about Hardiness anyway? But I ain't touching this kit until KR does something with him, it's a joke kit.

Disadvantages always make me laugh - 50% ms penalty while stance active. Why would you move anyway? It's not like you can die or something. No GM, which is unavailable in BG1? Needs to be a Dwarf, the best race anyway, only rivaled by Halflings? Lulz.

 

What's the EE team's excuse?

I'd guess: deadlines, too much focus on other stuff, too much work for EE1 left to do, too short of a budget to hire additional work power. Some members of original team are out of reach as well, some stuff has been lost.

 

My favourite example (besides hardiness stacking with itself) is blades getting Improved Bard song as HLA inspite of their supposed kit disadvantage being a song that doesn't improve with levels.

Lots of things stacked in vanilla. Armor of Faith, Spirit Armor (I don't know if Fixpack fixed Spirit Armor).

As for blades - try Rogue Rebalancing. Why some of stuff there wasn't included in EE I don't understand. At least it's made compatible. If they could include 1PP, why not at least parts of other mods?

Kits - in game you either have apsurd (Berserker, Archer, Barbarian, Blade), zero flavour (Paladin, Ranger, Thief, Bard, any mage kit), jokes (Beastmaster, Shapeshifter) and a few which I'd call balanced such as cleric kits and monk. Hence my high hopes for KR. EE just added one to apsurd, one to joke, then made a few extra which really don't fit anywhere - least of all in the category "a kit I want to play with".

[polytope]

Disadvantages always make me laugh - 50% ms penalty while stance active. Why would you move anyway? It's not like you can die or something. No GM, which is unavailable in BG1? Needs to be a Dwarf, the best race anyway, only rivaled by Halflings? Lulz.

 

...

 

Kits - in game you either have apsurd (Berserker, Archer, Barbarian, Blade), zero flavour (Paladin, Ranger, Thief, Bard, any mage kit), jokes (Beastmaster, Shapeshifter) and a few which I'd call balanced such as cleric kits and monk. Hence my high hopes for KR. EE just added one to apsurd, one to joke, then made a few extra which really don't fit anywhere - least of all in the category "a kit I want to play with".

 

Yeah, at least Barbarians have a real disadvantage of being limited to specialization in weapons (for players with un-nerfed GM) and chain mail armor - albeit this kit was also broken come ToB thanks to 80% DR with hardiness and the defender flail. Archers also have drawbacks - still overpowered mainly thanks to their called shots and absurd damages bonuses at ToB levels, so do blades prior to getting ToB HLA's (are you seeing a pattern here?). The berserker is the one with absolutely no disadvantages and it's still not a Dwarven Defender.

 

As for blades - try Rogue Rebalancing. Why some of stuff there wasn't included in EE I don't understand. At least it's made compatible. If they could include 1PP, why not at least parts of other mods?

 

Oh, I've got that mod and I like it. My point was that 12 years on Trent and co somehow introduced more of the same major balance issues that Bioware did with the release of ToB. C'mon, they had more than a decade worth of feedback to build upon. I wouldn't bash their work if it was a free mod, but for something marketed as enhancing Baldur's Gate II they've added a lot of unnecessary stuff and haven't fixed most of the original flaws in game mechanics and design.

[kreso]

In Davaeorn battle, he seems to have a tendancy to teleport away from line of sight from party, effectively making you fight Horrors without him bothering you. This only happens in the beginning of the battle (1st teleportation). Other than that, once he teleported near entrance point where 2 invisible PCs were placed. He then casted Teleport Field, and his flunkies refused to attack my characters (the ones visible and shooting arrows at them) by simply staying near Davaeorn and within Teleport Field AoE.

He doesn't leave Stoneskin or Remove magic scrolls behind, even tough Readme states otherwise.

Centeol uses Oil of Speed, but she cannot move or attack .

[kreso]

Some further (final) info on BG1 (BGT install)

- in Duralg's Tower some more creatures have potions, afaik they shouldn't:

Phoenix Guards (they should probably be some kind of Fire Elemental or similar, they also use potions like Power and similar)

Invisible Stalkers in Air Aspect challenge room also get and don't use them

When finishing the challenges, you get teleported to Chess Battle. For some reason, the battle starts immediately (enemies rush towards you even if you're still out of their line of sight). I welcome the challenge, but it's rather unfair since you need to pre-buff for Chess before you even "know" you'll get teleported there. Also, battle is nigh impossible without making everybody invisible.

Or start blasting everything with fireballs and detonation arrows.

Upon returning to Candlekeep, one can fight the Iron Throne leaders there. Making them hostile causes the entire floor to go hostile. I don't know if this is standard, intended behaviour.

Final battle vs Sarevok - enemies should probably use Invisibility detection much more often and early (they've got 2 mages, they should have at least 3-4 Invisibilty Purges). I'm not against Sarevok having a "invisibility detection via script" effect since an Assassin can finish this battle solo.

Semaj used "Improved Haste" on Tazok. All the power to that spell, but I'd prefer him focused either on Evocation or Enhancement (with strong preferance to Evocation), Imp.haste just isn't worth a slot here. Disintegrate, Flesh to stone, Chain Lighting and similar would be I guess.

Karoug seem to be immune to all weapons with IR installed but I don't know if this is SCS or IR doing, I think he wasn't immune to anti-werewolf weapons in v26.

In Undercellar battle vs Krysten and Slythe, Krysten vanished for a few rounds and then Dimension-doored near a PC. I couldn't find her anywhere until I saw "Dimension Door -PC" message, then she appeared.

AI doesn't seem to detect "Charm protection" item on a character (IR Greenstone) which makes them constantly use it against a charm-immune character.

Other than that, I didn't notice any bugs.

[DavidW]

Some further (final) info on BG1 (BGT install)

- in Duralg's Tower some more creatures have potions, afaik they shouldn't:

Phoenix Guards (they should probably be some kind of Fire Elemental or similar, they also use potions like Power and similar)

Invisible Stalkers in Air Aspect challenge room also get and don't use them

Elementals shouldn't; I'll muse on phoenix guards.

When finishing the challenges, you get teleported to Chess Battle. For some reason, the battle starts immediately (enemies rush towards you even if you're still out of their line of sight). I welcome the challenge, but it's rather unfair since you need to pre-buff for Chess before you even "know" you'll get teleported there. Also, battle is nigh impossible without making everybody invisible.

It's intentional - but I'm open to reconsidering it. If the component is working correctly then the chess-battle creatures don't get a chance to prebuff either, so it's at least fair.

 

Upon returning to Candlekeep, one can fight the Iron Throne leaders there. Making them hostile causes the entire floor to go hostile. I don't know if this is standard, intended behaviour.

 

Final battle vs Sarevok - enemies should probably use Invisibility detection much more often and early (they've got 2 mages, they should have at least 3-4 Invisibilty Purges). I'm not against Sarevok having a "invisibility detection via script" effect since an Assassin can finish this battle solo.

Will consider - though I'm nervous about making this battle too hard for some people. (An over-hard final battle can actually be an exercise in frustration, since at that point you're keen to reach the end of the story.)

 

Semaj used "Improved Haste" on Tazok. All the power to that spell, but I'd prefer him focused either on Evocation or Enhancement (with strong preferance to Evocation), Imp.haste just isn't worth a slot here. Disintegrate, Flesh to stone, Chain Lighting and similar would be I guess.

I don't use Disintegrate (except on SR installs). I could consider the others but they can make the battles a bit swingy (I'm generally a bit cautious about overuse of BG2 magic in BG1).

 

Karoug seem to be immune to all weapons with IR installed but I don't know if this is SCS or IR doing, I think he wasn't immune to anti-werewolf weapons in v26.

In Undercellar battle vs Krysten and Slythe, Krysten vanished for a few rounds and then Dimension-doored near a PC. I couldn't find her anywhere until I saw "Dimension Door -PC" message, then she appeared.

Pathing issue - she'll have wandered out of sight. High-level wizards who do that dimension-door to a player. Not a lot I can do about it.

 

AI doesn't seem to detect "Charm protection" item on a character (IR Greenstone) which makes them constantly use it against a charm-immune character.

Will chase.

Other than that, I didn't notice any bugs.

That's refreshingly low!

[kreso]

When finishing the challenges, you get teleported to Chess Battle. For some reason, the battle starts immediately (enemies rush towards you even if you're still out of their line of sight). I welcome the challenge, but it's rather unfair since you need to pre-buff for Chess before you even "know" you'll get teleported there. Also, battle is nigh impossible without making everybody invisible.

It's intentional - but I'm open to reconsidering it. If the component is working correctly then the chess-battle creatures don't get a chance to prebuff either, so it's at least fair.

It's working fine then - it is a fun battle all things considered.

 

 

 

Final battle vs Sarevok - enemies should probably use Invisibility detection much more often and early (they've got 2 mages, they should have at least 3-4 Invisibilty Purges). I'm not against Sarevok having a "invisibility detection via script" effect since an Assassin can finish this battle solo.

Will consider - though I'm nervous about making this battle too hard for some people. (An over-hard final battle can actually be an exercise in frustration, since at that point you're keen to reach the end of the story.)

The alternative is hide 'n' seek, and Sarevok can still be delayed with summons so there's still an option left.

Anyhow, do as you please - just a suggestion. After all, if he can be "unkillable" he might as well see invisible creatures.

 

Semaj used "Improved Haste" on Tazok. All the power to that spell, but I'd prefer him focused either on Evocation or Enhancement (with strong preferance to Evocation), Imp.haste just isn't worth a slot here. Disintegrate, Flesh to stone, Chain Lighting and similar would be I guess.

I don't use Disintegrate (except on SR installs). I could consider the others but they can make the battles a bit swingy (I'm generally a bit cautious about overuse of BG2 magic in BG1).

I guess it would be fine if Semaj would use such a spell on Sarevok, but Tazok is usually the worst possible target for this spell, since he is the easiest to kill.

 

AI doesn't seem to detect "Charm protection" item on a character (IR Greenstone) which makes them constantly use it against a charm-immune character.

Maybe it's the item itself (missing something SCS would patch), not the targeting. Character with it equiped would display a message "Charmed" and the appropriate animation, but wouldn't be influenced by it. I don't know. They do detect immunity to Confusion.

Other than that, I didn't notice any bugs.

That's refreshingly low!

Yup. I kind of "forced" myself through the encounters I generally don't do to find more bugs, but failed.

As a sidenote, arguably the single hardest battle was the one in Ulgoths's Beard hut just above Aec'Laetec upon returing the dagger, followed by Durlag's Dwarf guards (standardly painful. The little thief there has outstanding targeting...one wrong move, and your mage is chunked ) and Chess in Durlag (mostly due to surprise factor).

And please do give Davaeorn a Stoneskin scroll. Otherwise one has to travel to Ice island to get it.

[kreso]

Some bugs/errors for BG2:

Mods installed:

Ascension, Fixpack, BGT, IR/SR/KR, Refinements, BG2Tweaks ammo stacking, SCS (pretty much all components, full prebuff), aTweaks Undead/Mephits, Polytweak Mind Flayers and Trolls.

Tweaks of my own:

-Protection from Magical Weapons protects against all weapons, not only enchanted (I find mages who employ PFMW too easy otherwise)

- AI_detects_slowly set to 0

-dragons 5x HP

 

- Ruhk Transmuter used a sequencer with Stoneskin + double Fireshield. Fireshield animations did not show up. Other mages using this sequencer correctly display animations. Fireshield did take effect, however.

- Tanova, vampire mage in chapter 2 stands idle (I think this is due to "improved Vampires" component)

- in Firkraag's Lair, some golems can follow you down the stairs if they had not spawned earlier.

- Cernd dies when left to fight against Faldorn himself. She uses Ironskins, making him moot.

- in Umar Hills dungeon (Shade Lord quest) those spirits which give you Shadow Dragon wardstone drop potions. Assuming they're (un)dead, they shouldn't have those.

- Mind Flayers and Harper Ghosts also drop potions

- Sanik, the mage which gets killed in Brynlaw gets potions and is smart enough to use them. In turn, that makes the assassin slightly less lethal when hitting him with arrows.

- Sarevok in Spellhold Dream area also uses potions.

- Vampires display wrong string when they shapeshift ("Lord Fartinghton Roenal")

- low-level oponnents like Kobolds and Orc Shamans/mages use Detect evil fairly often. Given that this spell is useless, I assume this is wrong.

- Noble Djinni in Spellhold (room which opens by a painting, other rooms have Mind Flayer, Umber Holk and Troll within) starts casting Stinking Cloud to no avail, even tough he's locked and hasn't seen anyone.

- battle vs Irenicus in Spellhold - your own party gets targeted by Charm spells cast from your looney allies (Aphril etc.)

- Dream sequence after Spellhold is done (one, two, three etc.) - Bodhi, Sarevok, Irenicus, all drop potions.

- when leaving Brynlaw via ship, the ships gets boarded by Githyanki/Sahaugin. Githyanki benefit from improved scripts.

I'd really prefer this remained a "cutscene", not a short, but possibly leathal, battle.

- Kruin, the Githyanki mage who waits in the city upon return, botches up the game if approached and talked to under Improved Invisibilty spell.

- vampire mage in Chapter 6 who stands where Tanova stands in Chapter 2 (right outside the room with thorns) also seems to have a broken script.

- Bodhi can suffer from morale failure. In effect, this makes her unkillable since she then refuses to talk.

- after killing Bodhi, one gets ambushed by peasants which ask for Charname. They should attack, yet remain green-circled and stand idle until attacked.

- I was unable to complete Mind Flayer Underdark Lair since the game slowed down to 0,3 FPS. I don't know if this is caused by SCS or not.

 

Other than that, some toughts:

- vampires CON drain should last shorter. No battle lasts for that long as the constitution drain. I find them interesting, much improved than vanilla, slightly annoying with shapeshifts. Their "mesmerize" ability doesn't seem to be blocked by Charm immunity. It's hard business fighting them in early levels. I'd like that Dace Sontan doesn't get their scripting, he seems like an outcast anyway.

- mages could (should?) employ some anti-invisibility spells faster in battle.

- battles I found to be very fun (or hard, but it's the same for me) are:

Bodhi in Chapter 6 - the whole battle, both top floor and below, are great. Bit of excercise in suffering, but the challenge is really spot-on, espeically w/o a cleric or Mace of Disruption. Bodhi seems to be very resilient, it takes a long while to get her down. Due to the bug with morale break I had, I CTRL-y ed her from the start so she can say her line and die properly, and still the battle was a very close match. I enjoyed it a lot.

- Firkraag - I find him un-doable for now (level 17). He has 929 or so HP, and once I get Alacrity I'll try again. Sometimes he uses breath on a character immune to fire (or 127% resistant) which heals him instead.

- Planar Sphere - Warden is apperantly a very high level mage since he casts Time Stop. Still doable, but barely at level 11. It was fun, and the demon fight before him is also nice.

- Irenicus in Spellhold - this took only one reload - in first attempt, he attacked with Energy Blades during his Time Stop, killing my protagonist.

- Elder Orb in Underdark - this redefines pain. I don't see it getting harder than this. Immune to any weapon with Imp.mantle, immune to spells with Turning. I did beat it eventually, mostly thanks to IR (potions are undispellable). Otherwise, very hard and challenging. The fact that 3 Gauths and 2 Beholders were nearby didn't help any.

- worshipers of Ghaundaur, some slime battle in Ust Natha. This actually provided a very nice challenge. With that many priest casting Mass Heal, killing even one is hard.

- battle at the exit of Underdark. Even with Adalon banishing Glabrezu, this is hard, especially if you don't prebuff.

 

Other than that, few issues:

- casters sometimes use Charm/Confusion type spells on character wielding Lirarcor or similar stuff

- I don't really get "smart melee targeting". I had 2 fighters on my front line - one had an AC of -4, the other had -13.

The one with -4 had 130 HP, -13 one had 110. Melee enemies like Bodhi, Vampires, basically anything which uses "smarter" script always prefer the one with -13 AC. If anything, this isn't really smart.

- anti-magic mage scripting works splendidly.

[polytope]

- Noble Djinni in Spellhold (room which opens by a painting, other rooms have Mind Flayer, Umber Holk and Troll within) starts casting Stinking Cloud to no avail, even tough he's locked and hasn't seen anyone.

Presumably because he checks for proximity of Player1-6, even if he can't see them.

 

- I was unable to complete Mind Flayer Underdark Lair since the game slowed down to 0,3 FPS. I don't know if this is caused by SCS or not.

I played through here with my own (Polytweak) flayers and didn't notice slow downs, then again I was using v21.

 

- Planar Sphere - Warden is apperantly a very high level mage since he casts Time Stop. Still doable, but barely at level 11. It was fun, and the demon fight before him is also nice.

He always was level 18+, but his scripting for some reason seemed suboptimal in previous versions, he didn't have as many protections as a regular high level mage.

 

- worshipers of Ghaundaur, some slime battle in Ust Natha. This actually provided a very nice challenge. With that many priest casting Mass Heal, killing even one is hard.

 

This is one of the few interesting battles with priests IMO, because there's six of them it's difficult to interrupt all their casting by melee and they're magic resistant so can't shut them all down with silence or disrupt them reliably with area spells.

 

- battle at the exit of Underdark. Even with Adalon banishing Glabrezu, this is hard, especially if you don't prebuff.

 

I always fight these guardians before meeting Adalon, I don't like my whole party being teleported by Adalon right into their midst and in range of the Drow Wizard's chain contingency with horrid wilting. It's a memorable encounter anyway.

 

- I don't really get "smart melee targeting". I had 2 fighters on my front line - one had an AC of -4, the other had -13.

The one with -4 had 130 HP, -13 one had 110. Melee enemies like Bodhi, Vampires, basically anything which uses "smarter" script always prefer the one with -13 AC. If anything, this isn't really smart.

 

Mind flayers at least definitely go for the worst AC character, they kept turning to attack (invisible) Valygar before he could backstab them.

[DavidW]

Quick reply to only a fraction of this: targeting generally is based on class and percentage hp. I generally don't allow myself oracular access to AC or raw HP totals.