Thac0 -1 ?

[Ningengirai]

I'm just full of questions lately. Please bear with me.

I know, rudimentary, what THAC0 stands for ( and find myself again confused because NWN = anything BUT go for AC 0 ), so can someone please explain the circled values in the image to me? I know the number in parentheses behind THAC0 is the critical hit roll number, but it's the "-1" in the lower circle that makes no sense to me. It's Armor Class, I know that, but how can it be -1 there while it says 15 (12) in the description?

[Aerich]

"Thac0" is an acronym for "To Hit AC 0". It refers to the attack roll, which is a randomly determined number from 1-20; mimicking a 20-sided die used in tabletop D&D. So if a character with Thaco 12 attacks an enemy of AC 0, the character hits on any roll of 12 or better. The lower the Thaco, the better.

Re: the circled numbers, I'll explain the "Thaco: 15 (12)" first. The "15" refers to the character's "natural", e.g. class and level-based Thaco. The "12" is the "actual" Thaco, once modifiers are applied. Common modifiers include bonuses for high Strength, bonuses for high Dexterity if using a missile weapon, and enchanted weapons. So your character at the time the screenshot was taken had a combined +3 bonus to attack from one or more sources. This is an offensive statistic only. It only interacts with your enemies' AC, not your own.

The "-1" is indeed your AC. It is a defensive statistic, and is unrelated to your character's Thaco. A character's AC and Thaco do not interact in any way; they only interact with the Thaco and AC, respectively, of that character's enemies. Your AC of -1 is affected by your armor, Dexterity, and protective spells and items. The lower the better.

[Ningengirai]

Gawd. I always thought that "THAC0" actually meant "To HAVE Armor Class 0". That's why it always confused me, seeing that any other game I played always aimed to have as high an AC as possible. Thanks, Aerich, it makes a lot more sense now.

[Aerich]

You're welcome. Doesn't NWN (or at least NWN 2) use 3rd ed D&D rules? In 3rd ed, Thaco is done away with altogether, replaced by BAB, and the higher the AC the better.

[Ningengirai]

Originally Posted by Aerich

You're welcome. Doesn't NWN (or at least NWN 2) use 3rd ed D&D rules? In 3rd ed, Thaco is done away with altogether, replaced by BAB, and the higher the AC the better.

NWN 2 uses, as far as I know, 3.5 Edition DnD, while NWN 1 used some bastardized form of an older edition. Neither used THAC0, so yeah, BAB is something I'm more familiar with, though probably not as familiar as I should be. I played NWN for some years and there were a few changes in NWN2 that just threw me for a loop.

[Redrake]

In IWD we have 2E, or more likely 2.5E. BG1 uses 2E as it did IWD before HoW add-on. BG2 uses the 2E with some added improvements from 3E. IWD2 is 3E.