Hi,

My first pure D&D game.. :)
Bit confused about spellcasting mechanics...
Is there an equivalent of THAC0 for spellcasting?
How are spell failures simulated?

Also, whats the most efficient way to develop spellcaster as a DPS or support unit?

And also my party is now level 3 but there was no option to increase attribute points while leveling up - playing on normal difficulty.

Thanks.
7PCGamer

That's normal; your attribute points never increase on level up in this game.

(It's actually one think I dislike about AD&D in general, but not one of the most severe issues.)


Anyway:

There's no equivalent of THAC0 for spellcasting.

Many spells allow the target a saving throw, and if it succeeds, the spell has reduced or no effectiveness.

Some enemies have spell resistance, which will cause spells to fail on them a certain percentage of the time.

Furthermore, if an attack damages you while you're casting a spell, the spell will fail. (This is one of my most hated mechanics in this game.) Note that having 100% or more resistance to the damage type will not prevent this, but avoiding damage via Mirror Image or Stoneskin (or Protection from Magic Weapons, but you can't get that spell in BG:EE without cheating) will.

(I should point out, however, that Mirror Image does not protect against other non-damage effects of an attack, unless that was changed in the EE.)

okay so in case of spells the target will be making saving throws.. and if the throw is greater than its spell THAC0... the spell will have no effect on that target... is there some manual that lists down these spell THAC0s for various enemies.. my sleep spell has been failing more frequently in last few hours of gameplay

also is it correct that spells cast on party members will never fail?

There isn't such a thing as spell THAC0. A saving throw is just a d20 roll that is compared to the target's corresponding saving throw, and if the roll is greater than or equal to the target's saving throw value, the save is successful. (This means that lower is better for saving throw values.)

With that said, some spells do give bonuses or penalties to saving throws, and they should be mentioned in the spell description.

Sleep will only work on low level targets (check the spell description); perhaps you're fighting enemies that are too high level to be hit with that specific spell. Magic Missile, which has no such restriction and does not even allow a saving throw, might be a better choice at some point. (I note that, in BG2, Sleep isn't even worth bothering with.)

Spells cast on party members have no protection from failure; however, most of the spells that you would ordinarily want to cast on your own party members do not allow saving throws or spell resistance, so they won't fail if you can get the spell off.

Yes I figured out ,. the spell description says that 'Monsters with 4 Hit Dice or more are unaffected.'... now Hit Dice = Level .. in AD&D lingo.. i was under the impression that some monsters who can roll four attack dices are not affected. Now i need to figure out what does AD&D means by Monster...

does it make sense to first read the AD&D book before playing this game?

Just read spell descriptions and play the game. You'll be able to focus on efficiency on your 20th playthrough.

Stronger monsters tend to have better saves, so it may also be a case where the monsters are making their saves more often. In any event, Sleep's usefulness will drop off as you encounter stronger creatures, so you'll eventually want to swap it out for other spells.

"Monster" is a generic term to refer to your adversaries, not a technical term referring to specific kinds of enemies (though "Monstrous [X]" can be a term for a particular set of enemies). For example, the "Hold Person" spell can only paralyze humanoid creatures (generally anything similar to human in size, shape, and basic power, like elves, orcs, dwarves, and halflings), but "Hold Monster" has a chance of paralyzing anything that isn't straight up immune (undead can't be held, being immune to enchantments, but a giant could be held). Most enemies are not humanoids, but the term "Monster" can apply even to humanoids. If you got in a fight with an elf leading a pack of basilisks, then they can be collectively referred to as "the monsters".

Hit dice and class level roughly correspond, so a 5th level Thief and a monster with 5 hit dice will both be unaffected by Sleep. In the absence of class levels, hit dice are the number of dice a monster "rolls" for hit points (though hp is set in the cRPG), not its number of attacks. Generally speaking, a 5 HD monster is going to have more hp than a 2 HD monster, though the 2 HD monster might have more attacks in a given round. Read through the game manual to get a feel for the mechanics. You don't need to read all the spell descriptions (unless you want to), just focus on the mechanics for playing the game. It would be a good idea to browse through the spells for each spell level you can cast, so you have an idea what each spell does.