Bacon Bits
Hero
I have not read the rest of the thread; however, I have opinions.
No, it's not just as complex as the current method. It's only the same complexity when you already know the target's AC. Since AC varies between targets and is typically a secret number until the players manage to work it out, THAC0 is not less complex. Players can't do die roll + AC >= THAC0. Players have to do Die roll - THAC0 = AC hit. Except that's wrong. They actually have to do THAC0 - Die roll = AC hit. Did you notice the error while reading, or did you have to stop to think about it? Is it obvious which is correct? If your THAC0 is 15 and your modified roll is 13, is it easy to intuit while rolling the dice that you hit AC 2 and not AC -2? Not really. It's hard to look at the dice and say, "Okay, that's not possible you must've done the maths wrong because that result is way off." You can't do that because 90% of the time your results are between -5 and 5. All your numbers look the same. And now you add in a modifer, and it gets really complicated. See, it's really easy to confuse THAC0 - Die roll - 1 = AC hit and THAC0 - (Die roll - 1) = AC hit. The room for math errors in how people actually use THAC0 is significant.
The real problem with THAC0 is that the "easy" mode formula of die roll + AC >= THAC0 conflicts with player nature. When players roll an attack die, every player -- and I do mean every player -- wants to know "What AC did I hit?" That's the question they always pose. It's one of the most common questions asked at the AD&D table. Players can't measure in their performance *against the other PCs and NPCs* without doing that step. In order to understand how well their character is doing -- how powerful they are -- knowing the target number they reached is vital. THAC0, in it's "easy" mode, seeks to obscure that information from the player by design. Gygax assumed the player would never know their THAC0. That's why the charts were in the DMG. Gygax assumed only the DM would determine the outcome of an attack because the DM would be in total control of everything. In reality, that's too much burden on the DM to look up tables all the time. So everybody made the players do it. Except the players want to know how well they're doing. Unless they roll high or low, they won't know. And then they'll only know they rolled high or low.
The lesson of THAC0 and descending armor class is clear: You cannot design an action resolution system around how you want people to play. You need to design them around what makes game play operate swiftly, intuitively for the players and the DM, it must be easy to evaluate by the players and DM so they can understand the consequences of modifiers, and it must help all players and DMs at the table understand what's going on and maintain the suspension of disbelief. It must be fast to resolve, it must not be prone to simple math errors, and it must not occupy more game time than it absolutely must. THAC0 and descending armor class essentially do none of that.
No, it's not just as complex as the current method. It's only the same complexity when you already know the target's AC. Since AC varies between targets and is typically a secret number until the players manage to work it out, THAC0 is not less complex. Players can't do die roll + AC >= THAC0. Players have to do Die roll - THAC0 = AC hit. Except that's wrong. They actually have to do THAC0 - Die roll = AC hit. Did you notice the error while reading, or did you have to stop to think about it? Is it obvious which is correct? If your THAC0 is 15 and your modified roll is 13, is it easy to intuit while rolling the dice that you hit AC 2 and not AC -2? Not really. It's hard to look at the dice and say, "Okay, that's not possible you must've done the maths wrong because that result is way off." You can't do that because 90% of the time your results are between -5 and 5. All your numbers look the same. And now you add in a modifer, and it gets really complicated. See, it's really easy to confuse THAC0 - Die roll - 1 = AC hit and THAC0 - (Die roll - 1) = AC hit. The room for math errors in how people actually use THAC0 is significant.
The real problem with THAC0 is that the "easy" mode formula of die roll + AC >= THAC0 conflicts with player nature. When players roll an attack die, every player -- and I do mean every player -- wants to know "What AC did I hit?" That's the question they always pose. It's one of the most common questions asked at the AD&D table. Players can't measure in their performance *against the other PCs and NPCs* without doing that step. In order to understand how well their character is doing -- how powerful they are -- knowing the target number they reached is vital. THAC0, in it's "easy" mode, seeks to obscure that information from the player by design. Gygax assumed the player would never know their THAC0. That's why the charts were in the DMG. Gygax assumed only the DM would determine the outcome of an attack because the DM would be in total control of everything. In reality, that's too much burden on the DM to look up tables all the time. So everybody made the players do it. Except the players want to know how well they're doing. Unless they roll high or low, they won't know. And then they'll only know they rolled high or low.
The lesson of THAC0 and descending armor class is clear: You cannot design an action resolution system around how you want people to play. You need to design them around what makes game play operate swiftly, intuitively for the players and the DM, it must be easy to evaluate by the players and DM so they can understand the consequences of modifiers, and it must help all players and DMs at the table understand what's going on and maintain the suspension of disbelief. It must be fast to resolve, it must not be prone to simple math errors, and it must not occupy more game time than it absolutely must. THAC0 and descending armor class essentially do none of that.
