How does THAC0 work ?

[Jaguar Sprint]

I just got neera into my group and saw that she has a + in using staves...then I see that her thac0 is 23 with +5 from proficiency ??? Whats the logic here ?

[Pepsu]

Its chance to hit against 0 armor class and you roll d20 dice
also lower is better

[martin77]

and initiative? the higher number the better?

[Včelí medvídek]

Originally posted by martin77:

and initiative? the higher number the better?

There is no initiative in Bg1/2/EE

Weapons with lower speed go before weapons with higher speed in scope of single round (10 seconds].

Eg. dagger with speed 2 will finsh attack animation 2 seconds in the round and go before 2 hand sword with speed 10 that will finish at very end of round.

Once characters have more APR the time is divided by number of attacks and weapon speed can be in general ignored.

[martin77]

Originally posted by Včelí medvídek:

Originally posted by martin77:

and initiative? the higher number the better?

There is no initiative in Bg1/2/EE

Weapons with lower speed go before weapons with higher speed in scope of single round (10 seconds].

Eg. dagger with speed 2 will finsh attack animation 2 seconds in the round and go before 2 hand sword with speed 10 that will finish at very end of round.

Once characters have more APR the time is divided by number of attacks and weapon speed can be in general ignored.

ok thanks.
in the german version there is in the description for a longsword: Initiative- factor : 4
bastardsword initiative - factor 7.

so this means the seconds after the action of this weapon for one swing is finished?

[Včelí medvídek]

Originally posted by martin77:

so this means the seconds after the action of this weapon for one swing is finished?

Simply say - yes. With all start at 0. But as mentioned once you have eg. 2 attacks per round the time segments are effectively halved.

it is in general negligible stat.. in dozens of games of BG1 and BG2 i have never ever considered speed of weapon as something to consider. In theory you can for example hit the enemy with dagger than run away until next round, rinse and repeat and enver give enemy chance to roll hit... in praxis you will probably never do or need anything like that (unless you solo on TOB or stuff like that)

[kaiyl_kariashi]

weapon speed generally only matters for backstabbing or doing hit and run with a 2-range weapon.

1-range weapons can pull it off if the enemy's weapon is slow enough, but much harder to do.

[Wicket W. Warrick]

I confirm and agree.
I never consider speed factor, but some weapons with low speed factor have an advantage hitting first. For example celestial fury because you stun the character before he acts. Anyway it is a minor advantage.
In general having a weapon with low speed factor brings to attack first and so getting hit a little less, but it is something difficult to notice.

[Noob Herder]

Originally posted by Gnarl:

People and monsters and such have an Armor Class, that's the AC0 part of THAC0. It usually goes from about 10 to 0 to -10. With -10 being the highest, and only the most dangerous monsters or magically enhanced adventurers could get that high, and 10 being some regular guy no armor.

So a 20 side dice is rolled. The higher the number the better. A 20 always hits, and a 1 always misses.

If your a mage and your THAC0 is 23, then you minus the AC of what you are fighting. So, the mage swinging on regular guy who has AC10, you need a 13 or better to hit him. So you a mage who didn't study weapons much can hit a regular guy less than half the time. It kind of makes sense. That's the "To Hit" part or TH of THAC0.

But if you fought an elite body guard of a noble who maybe was AC0, then the same mage would have to roll a 23 to hit him. But there's only 20 possible rolls on dice, so you only hit on a 'natural' 20. 20 always hits rule. It makes sense cause your mage is not good with weapons and he's taking on a champion level guard guy who dedicated his life to combat.

10/10 explanation. It's always bothered me how confusing the wording and logic is.