Quote:
Originally posted by Xero279:
Quote:
Originally posted by Dundee Slaytern:
THACO - AC = Number to beat on a 1d20
-4 - -4 = 0
Therefore, you will never miss except on a Critical Miss, which is a roll of 1 on a 1d20.
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Ya, that makes perfect sense dundee, so if it were -5 - -4 = -1, then you would only miss on a critical miss too, right?
Edit: spelling[/QUOTE]That's correct. What's missing here is that THAC0 stands for "To HIT AC:0", so it's the value you'd need to roll on a 20-sided die (i.e. 1-20 on a random number generator) if your opponent had AC:0. If your opponent has AC:2, you need to roll 2 less (so if your THAC0 is 5, vs. AC:2 you only need a 3 to hit). Similarly, if your opponent has AC:-2, you need to roll 2 higher (so, your THAC0 is still 5, vs. AC:-2, now you need a 7).
The formula To Hit is "THACO" minus "opponent's AC", but if "opponent's AC" is negative, you get 5 - (-2) & the double-negative turns into a positive (5 + 2), so you need to roll a 7 in this case.
Your THAC0 is only "useful" if your opponent has exactly Armor Class:0 - then your To Hit number is exactly equal to your THAC0. Otherwise you have to modify your To Hit number, by subtracting the target Armor Class. This table may help, for a character with a THAC0 of 5...
opponent AC...........roll needed
-3................8
-2................7
-1................6
0.................5
1.................4
2.................3
3.................2
4.................1
5.................0
So, this character hits AC:0 on a roll of 5 (or better) on a d20 (1-20), just as his THAC0 indicates. If he's facing an opponent with AC: 5, he needs to roll a 0 to hit, so the only way he can actually miss is on a Critical Miss (a roll of 1), which always misses. If he's facing an opponent with AC:-3, he needs to roll an 8 (or better) in order to hit.
This is one area where 3rd Edition makes more logical sense, although, IMO, it may be the only area. [img]smile.gif[/img]
- Imrahil
[EDIT: spaces in the table didn't work, so I added "..."]
[ 03-07-2003, 12:33 AM: Message edited by: Imrahil ]