STR is all important to spell casters. Once they can cast Quickness on themselves they can cast as many spells in one round as they have movement points, so STR becomes much more important than in the early game.
Also important for the fighter types, of course, since the more movement points they have the more attacks they will get each round if Quickened, although it may not be worth spending lots of gold to increase MP from for example 5 to 6.
Also make sure to hoard the regular STR potions; they are crucial in the most difficult fights.

IIRC the specal STR potions were not shown as especially valuable, which I guess is why I was fooled.

Sounds like I should prioritize my spellcasters when training strength, then. Will do.

I haven't been doing this so far, so thanks for the warning!

There must be some way to tell them apart. A different name?

I've now defeated the Troll King, although I still have more of the cave to explore. It wasn't a particularly hard fight. He had a rod of create fire, but many of my characters were fireproof, and his troll army was most definitely not. Also, I've started using more buff spells in dungeons (they expire too fast outdoors). I used to only cast Armor on everyone, but now I'm also casting Strength on my fighters and Haste on everyone. I was already doing well in most fights, and this makes them even easier.

They have different, but similar names, which is why I was fooled.

I found a potion of gain intelligence, which did seem to raise one of my mage's intelligence permanently. So I'm guessing they're called potions of gain strength, as opposed to potions of strength. I haven't come across one yet.

I'm on to the next island now. I must say that the rest of the first island was pretty boring. Samey caves filled with samey enemies. Lizardmen, hobgoblins, orcs and ogres were basically the same, although the ogre cave was a little more interesting to explore compared to the others. Fortunately, this new island is more interesting. I cleared out the cultists' hideout and it was a lot more fun to explore, and now I've found a second town that's tasked me with taking out some bandits.

My mages are now able to cast Boulder fairly reliably, and it's powerful enough to knock out most enemies with a single shot. I've even managed to cast Death Bolt a few times on tougher enemies. I've taken to having my (hasted) melee fighters charge forward in most fights; the enemy rarely gets around them, and my mages can blast anyone that does. I've also started having them aim for the brain, which means they can sometimes drop enemies with a single attack. My priests now try to charm enemies as a way of taking them out of the fight, but I wish a knew better offensive spells for them, as my party rarely gets hurt (I cast armor on everyone) so my priests often feel like they don't have anything to do.

I haven't found any new items worth using in a while. It seems like most treasure is just valuable stuff I can sell for money, so mostly I've been training my party rather than equipping them better. I did find an iron broadsword though, which I'm hoping to enchant for fighting demons. I also still don't know how to cast Quickness. I'm curious: right now, if a party member is next to an enemy, their movement points are reduced to one. Does that mean that even if they had Quickness, they'd still only get one attack per turn? Or does Quickness override that? Even if melee fighters do only get one attack per turn, my archer will still be able to fire rapidly, which will make her a lot more useful. My packs are currently overflowing with arrows and bolts, so I can afford to fire faster.

Anyway, this new island is a lot more fun so far, which is good. It's getting me excited to push onwards again!

I remember learning Quickness from a sorceror (in some tomb, I think). It was a nasty surprise when he spammed Death Bolts.
Quickness should override the movement rule.

I don't know if I have mentioned it before, but the Demon World is a real pain to navigate, and you may want to use a map (I think there's a map in the hint book) to get through it as quickly as possible.

I have heard this elsewhere, and I'm already planning on using the map. I think I have a ways to go before I get there, though.

Well, I just met a sorcerer who is spamming death bolts. But he didn't cast Quickness first, it just seems he starts the battle with Quickness already on. He's also invisible and surrounded by demons.

I don't see how I can win this fight without knowing Quickness myself, so I guess I have to go explore elsewhere for now. It's a bummer since his henchmen were easy to deal with. But the last obstacle between me and the treasure hoard is an impossible battle where several of my party are killed before I even get a chance to act.

EDIT: Was just pondering this when I had an idea. Turns out I was able to make an educated guess and figured out the Quickness spell! So we'll see if I can win this fight now.

...and, yes. He still killed one my my characters, but after that it was easy. It is getting annoying casting all my buff spells on everyone though. They keep expiring as I cast them. I'd like to get Quickness, Haste, Strength and Armor on everyone, but it seems nearly impossible to do that before earlier ones expire. Sigh.

I've noticed my characters have started to lose some strength every round during battle. It's most noticeable for my fighters. Is this a side effect of casting Quickness on them? Or is it something else? I can't seem to find any mention of it anywhere, even in the info booklet.

I'm bothering some birdmen at the moment.

Yes, that's the price you pay for Quickness in combat. So having potions of regain strength can be useful even for fighters. Nasty buggers. Hard to hit.
Met any Phoenixes yet?

Well, that's really annoying. And not documented anywhere. Is there any way to un-cast quickness on characters once their strength is low? It basically makes it impossible to recover if they lost all their strength. Resting for a turn regains some strength that's immediately lost again.

Yeah, I'm done with the birdmen now. Only one phoenix managed to actually attack one of my characters. The others succumbed to Boulders first. I must say I'm finding Boulder to be much more useful than death bolt right now. Easier to cast, works on demons... I guess when my magic skill is higher and enemies have more health, death bolt will be better. Right now boulders are knocking out pretty much anything in one hit. A few hits for certain really tough enemies, but that's still easy with Quickness.

I don't recall it being a problem (and I checked my old thread).
It's been a while since I played, so it's possible there is some other explanation your characters losing strength. Or maybe their starting strength is too low.

I confirmed that characters without Quickness on do not lose strength each turn. It looks like it's just 1 strength lost per turn, but there was one fight that caught me just as the party ran out of food so everyone's starting strength was low, and I had trouble regaining strength.

Accoring to the in-game help screen, resting for a turn in combat regains 1d6 strength, so I might have just gotten unlucky when resting. If I only regained 1 or 2 strength from resting and then lost 1 again due to Quickness, it would seem like I could never recover. But I guess in reality it's just slower.

Anyway, with proper preparation I should be able to handle it.

EDIT: Never mind, I just saw one of my fighters lose 6 strength in one turn due to Quickness. So now I'm guessing that it causes characters to lose 1d6 of strength each turn. So it's the luck of the roll that determines how much one regains when resting with Quickness active.

I'm still plugging away at Nahlakh, in case anyone is interested. I just started exploring the third island.

I was starting to get a little bored, because I was basically using the same combat strategy for every fight (Quickened mages and priests blast everything from afar before it can even move), and it felt like I was never finding any useful equipment for my characters, so the only progression was the slow advance in skills. And at this point my fighters are all good with their weapons, so there seems to be little change as they get more skilled.

But the third island is more interesting so far. This is helped by finally getting a chance to turn all my money into training, so my party all has higher dexterity, health (I went back for that) and strength. My fighters are much less encumbered now and can actually close the distance to enemies before my spellcasters kill everything. Also, fighting in the jungle changes up my strategy a bit since trees block line of sight for most spells. And of course I found a certain powerful item at the end of the last island which is pretty cool.

I got unlukcy with random drops for my axe-and-shield dwarf though. He's still using an obsidian axe which is pretty bad at this stage. If I'd even found a regular iron axe I would have enchanted that and made it his main weapon, but I still haven't found any axe worth enchanting. Hopefully he'll find something on this island. It's a bit of a bummer that characters who specialize in one weapon are completely useless with others. He's an axe expert but can't swing a mace to save his life. It forces players to pick a weapon class and guarantees that a lot of loot will be useless.

I am still enjoying the game overall though. I just wish for a faster pace; there are lots of battles with very slow progression. Mostly I'm looking forward to the incredibly tough battles at the end of the game that I've heard about. Those will be a satisfying test of my party.

Looks like quite a big game. Is it? How big is the world so far?
And how is the character progress, is it very strict or you can munchkin your way through the game if you want so?