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Let's Talk About THAC0

The following observations are inarguable, as they are the result of maths and/or tables:

1. THAC0 is clearly superior.

2. However, it is only superior to the extent that it is derived from the ur-superior system, tables of attack matrices.

3. Tables > everything else.

4. In addition, armor classes should go down (lower IS better), in the way that God and Gygax intended.

5. -10 is something to be eternally lusted after, is it not? Is there no place in modern Dungeons and Dragons for negative numbers?????? We must no longer cater to the tyranny of the innumerate.

6. Finally, THAC0 is just fun to say. SAY IT! SAY IT NOW!

I rest by case, which is both indisputable, and indubitable.

You're welcome.
I endorse this message
 

lowkey13

Exterminate all rational thought
I endorse this message
Crom, I have never prayed to you before. I have no tongue for it. No one, not even you, will remember if we were good men or bad. Why we fought, or why we died. All that matters is that we used THAC0.

That's what's important!

THAC0 pleases you, Crom... so grant me one request. Grant me a negative armor class! And if you do not listen, then the HELL with you!
 

Sacrosanct

Slayer of Keraptis
I'd say yeah, that's typically the way it was done. Prior to Thaco, you'd have a matrix on the DM's screen, so, again, you call out your attack number, and the DM consults the matrix to tell you if you hit or not. AFAIK, that's typically the way it was done, so, virtually all the math was dumped on the DM to figure out. .
This is not true. At least as early as 1980, the character sheets had this info on them. See the examples above. So players knew what AC they were hitting from pretty much the beginning, at the very least when the game started to really grow and take off, and 9 years before THAC0 became a thing
 

Hussar

Legend
This is not true. At least as early as 1980, the character sheets had this info on them. See the examples above. So players knew what AC they were hitting from pretty much the beginning, at the very least when the game started to really grow and take off, and 9 years before THAC0 became a thing
If you used the published character sheets, sure. We never did. We always hand wrote our character sheets. No fancy schmancy TSR sheets for us. :D

I mean, if everyone already had that number, why did the DM's screen have the matrixes? Seems like a total waste of space.

But, hey, you did it your way, I'm just reporting how we did it.

/edit to add

Funnily enough, [MENTION=15700]Sacrosanct[/MENTION], if you look at the AD&D sheet you posted, you'll see that the player didn't actually fill in the numbers for hitting various AC's. :D
 

HarbingerX

Villager
Personally once I discovered Target 20 System, I never looked back. http://www.oedgames.com/target20/.

1. Works with descending AC.
2. Doesn't need any tables or lists, just the player's single +X to hit.
3. Keeps monster AC secret.
4. Mentally fast as it uses only addition of small numbers (<10)

It's what THACO should have been. Player rolls, adds their bonuses, then tells DM answer. DM add the monster's AC in their head and if the answer is 20 or higher, the player hits.
 

Sacrosanct

Slayer of Keraptis
If you used the published character sheets, sure. We never did. We always hand wrote our character sheets. No fancy schmancy TSR sheets for us. :D

I mean, if everyone already had that number, why did the DM's screen have the matrixes? Seems like a total waste of space.

But, hey, you did it your way, I'm just reporting how we did it.

/edit to add

Funnily enough, [MENTION=15700]Sacrosanct[/MENTION], if you look at the AD&D sheet you posted, you'll see that the player didn't actually fill in the numbers for hitting various AC's. :D
They also only listed 4 spells and clearly judging by their stats, were playing fast and loose monty haul. Point being, is that from pretty much the start, the players did have that info. They didn't need to ask the DM and the DM didn't need to consult the matrix for every PC attack made.
 

billd91

Hobbit on Quest
BTW, was it really that hard to get into negative AC's in 2e? Full plate and shield was AC 0 and that was generally affordable by about 3rd or 4th level. Add in any magical protection (+1 shield, ring of protection) or even a 14 Dex and you have a negative AC. Drilling your AC down to near -10 was certainly do able in the games we played. By about 7th-10th level generally.
Maybe not, but just try to explain it. I was enough of a math geek that I got it. But try to explain it to someone who's new and deal with questions like: "So... I add up the +1s, +2s etc and then subtract them from my AC but I add the defensive modifier from my Dexterity to my AC? ...Is adding good or is subtracting? This is stupid."
Yeah, that sucked. The armor class system was full of PITA.
 

billd91

Hobbit on Quest
Maybe for your group. For as long as I’ve been discussing games on the internet there have been people who claimed to have genuinely preferred THAC0. Personally, I didn’t start playing until 3.5, my analysis is based purely on my understanding of game design and psychology.
I think a lot of it comes down to the psychology. D&D's ACs and THAC0 were proud nails. They didn't make much intuitive sense - they just were and mastering them was a cultural marker that gamers of a certain type (mainly the ones who mastered it) valued.
 

billd91

Hobbit on Quest
Did you do it differently? I guess I never considered the possibility that the DM might just ask you to roll and tell him the number you got and your THAC0, do the math himself, and tell you if you hit or not. That sounds awful, it’s no wonder it developed such a bad reputation if folks were doing it that way.
I generally subtracted my die roll from my character's THAC0 to get what AC he hit. Other players I knew tried the same with varying results thanks to the conceptual challenges lots of people have dealing with negative numbers. So I don't know exactly where your misunderstanding is coming from... but the main issue here is the DM wasn't telling us what our target was. We were telling him what target we hit.
 

Azzy

Explorer
I always thought it was unnecessarily backwards. The change in 3e was like, "about damned time".
 

Charlaquin

Goblin Queen
I generally subtracted my die roll from my character's THAC0 to get what AC he hit. Other players I knew tried the same with varying results thanks to the conceptual challenges lots of people have dealing with negative numbers. So I don't know exactly where your misunderstanding is coming from... but the main issue here is the DM wasn't telling us what our target was. We were telling him what target we hit.
Ahh, ok. Yeah, that sounds generally worse than adding your attack bonus to your roll result and saying what AC you got. Of course, both sound worse to me than the DM telling you what AC you need to hit and telling them if you hit or miss. And when doing it that way, it seems that doing the math to figure out what number you’ll need to roll on the die first and then rolling would be the ideal way to execute that. Of course, I recognize that a lot of DMs don’t like to tell the players the ACs of the monsters or the DCs of the checks. So ya know, YMMV.
 

Lanefan

Victoria Rules
I'm about as old-school as it gets and I've never used or liked THAC0.

As a DM, I just use the 'rule of 21' (if the roll + bonuses - penalties + target's AC + attacker's fight level (a.k.a. BAB) adds to 21 or higher it's a hit).

As a player, I'd rather let the DM worry about it. It's what she's there for. :)

EDIT TO ADD: That said, I've never yet had a problem with the concept of descending and-or negative AC. I did take the -10 cap off, however; a character in my current game is running around at -12 but it doesn't always help him... :)
 
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Lanefan

Victoria Rules
Moreso than the maths, which as many people have pointed out (and is relevant, by the by) is a tad more complex, the reason why BAB (and especially Proficiency Bonus) is much simpler is because the numbers are right there in your class/general level up descriptions.
Which represents a big underlying philosophy shift: it moves that information from the DM side (combat matrix) to the player side.

I'd rather it stayed with the DM.
 

Lanefan

Victoria Rules
Did you do it differently? I guess I never considered the possibility that the DM might just ask you to roll and tell him the number you got and your THAC0, do the math himself, and tell you if you hit or not.
How else do you do it? It's not like the combat matrix is player-side information.

In this instance telling the DM your THAC0 is needless info for her. Just tell her your roll and your then-applicable bonuses and-or penalties; and she'll worry about a) the combat matrix and b) any bonuses/penalties that you don't know about.

That sounds awful
Why? Less for the players to worry about, and once you've done it for a session or two as DM it's as easy as pie.
 

Charlaquin

Goblin Queen
How else do you do it? It's not like the combat matrix is player-side information.
Err... We were talking about THAC0, which is player-side information. Also, the character sheet posted up thread with a space to fill out rolls required to hit targets of various ACs would seem to me to indicate that the combat matrix (or at least the part that was relevant to your own character) was functionally player-side.
In this instance telling the DM your THAC0 is needless info for her. Just tell her your roll and your then-applicable bonuses and-or penalties; and she'll worry about a) the combat matrix and b) any bonuses/penalties that you don't know about.Why? Less for the players to worry about, and once you've done it for a session or two as DM it's as easy as pie.
It mucks up the dramatic tension of the die roll, even worse than adding a modifier does. If you know the target’s AC and your THAC0, you can quickly work out what number you need on the die, and then you get the craps-esque rush of knowing exactly what number you want to see on the dice, holding them in your hand, giving them a good shake, and holding your breath for the result as they roll. That’s a viscerally satisfying experience right there because it perfectly follows that dramatic tension curve that our human brains go bananas for.You kind of get that with BAB, but there’s an extra step of having to add a modifier to the die roll to figure out the total. That really messes with the drama of the die roll in a way that isn’t immediately obvious to most people but affects them nonetheless. That’s why critical hits are so exciting. It’s not just the fact that you do extra damage, it’s also the fact that they fix the broken dramatic tension curve. You see that 20 and immediately know you got a hit. The natural 20 is more exiting in an of itself than the actual damage, because it tickles your brain just right.The way you describe it, the die roll isn’t exciting or satisfying at all, it’s just a formality you have to observe before the DM can tell you what happens. At that point it would be more interesting (or at least less busy work) to just let the DM roll the die too, because you’re not getting any of the dopamine that rolling dice normally triggers.
 

rgoodbb

Explorer
THAC0 - Don't be so negative....

Seriously though, my maths is quite poor and I started with THAC0 and never had any issues with it. It was just how the game was played and I never knew otherwise then.

I have met people since who like to dis THAC0, who have never actually used it.

I miss THAC0
Weirdly, as a player I also miss Level Drain. Go figure.
 

TallIan

Explorer
Kidding aside, I never met anyone who didn't pronounce it THACK-OH. Maybe it's a midwestern thing.
Possibly, it seems to vary by region. When I was in South Africa we said THAK-OH; when I moved to the UK people (who were old enough) said TAK-OH; but at university I knew a guy from elsewhere in the UK who said THAYK-OH.
 

TallIan

Explorer
I feel sorry for poor old THAC0. It has a bad reputation for being complex, when it's exactly as complex as the current method!
I wonder how much of the bad rap comes from the varying AC of the edition - flat footed; surprised; attacks from the rear - rather than THAC0 being complicated.

People only remember AC being more complicated and it’s easier to blame one thing.
 

Oofta

Title? I don't need no stinkin' title.
I wonder how much of the bad rap comes from the varying AC of the edition - flat footed; surprised; attacks from the rear - rather than THAC0 being complicated. People only remember AC being more complicated and it’s easier to blame one thing.
I kind of liked flat footed, surprised and facing. It added a bit more tactics. Never cared for calculating THACO.As far as the "only people who didn't use it dis it" ... umm ... no. My wife learned to play with 2E and was quite happy with the change in calculation with the advent of 3, as were several other people in my group at the time. It accomplished the same goal while being more complex for most people.
 

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