AC vs HP using probabilites [Archive] - Wizards Community

AC vs HP using probabilites [Archive] - Wizards Community

Post/Author/DateTime Post
Xronos
10-07-05, 03:50 AM As the title says I wanted to find out which of the two is more important. So I came up with the idea to calculate some probabilities, with the help of course of a computer. And here is my model. Two characters A and B with the same stats battle each other.
Attack = 0
Damage = 1
HP = 1
AC = 10
Player A plays first. He has of course the advantage. The probability to survive over many battles is from 60% to 70%, while for player B is from 40% to 30%.
So I would like to make these probabilities almost the same.
If I was increasing HP, I should increase them to about 200 or more.
But the AC needed only 17.
This means that with a little increase in AC you have the same result as if you increased HP a lot more. (OK nothing new;) but I am going to run other cases too.)
Does anyone has made similar thoughts, calculations or run many times the same battle over and over? (Ideas for probabilities and computer sinmulations would be great)
20102000
10-07-05, 09:18 AM I did look at something similar awhile back, with level progression.
As you rise in levels your hp go up, you # attacks go up, and your + to hit goes up. You can also increase your damage and AC. However even with Min/Maxing the rate of increase on AC and damage is slower.
What this all means is that at higher levels AC can be irrelavent. If your AC is 20, and a monsters to hit is +20/+15/+10/+5 its chance to hit is 95%, 75%, 50% and 25%. Or 2.45 hits per round. A +1 to AC will reduce the hits per round by 0.2. While a +1 to damage with increase damage by 2.45 per round.
So AC related to ,bonus hit chance is an important measure. And tends to decrease as you rise in levels.
Also damage becomes more important. At lower levels you might not hit or be hit, so the damge is less imortant. While at higher levels, you get hit, so the damage + becomes more important.
Going through all the figures helped me understand the usefulness of power attacks, and combat expertise, especially at higher levels.
Edymnion
10-07-05, 02:57 PM Its pretty simple, IMO.
You will never have a character with an AC by higher levels that stands even a chance of stopping every attack that comes his way (usually its only good for stopping last few hits in a full attack).

Hence, hitpoints are a much bigger, and much more important buffer against death than AC is.
Dragonsblood
10-07-05, 03:14 PM I think your calculations are a bit off....you're saying that the guy with 1hp and 17ac will have a better chance of beating the guy with 200hp and 10ac. I don't think so.
BladeDrinker
10-07-05, 11:55 PM You also have to consider the fact that AC doesn't protect you from spells, breath weapons and the like. HP's do. One bag of caltrops and your 1 hp character would be screwed.

Post/Author/DateTime	Post
Xronos 10-07-05, 03:50 AM	As the title says I wanted to find out which of the two is more important. So I came up with the idea to calculate some probabilities, with the help of course of a computer. And here is my model. Two characters A and B with the same stats battle each other. Attack = 0 Damage = 1 HP = 1 AC = 10 Player A plays first. He has of course the advantage. The probability to survive over many battles is from 60% to 70%, while for player B is from 40% to 30%. So I would like to make these probabilities almost the same. If I was increasing HP, I should increase them to about 200 or more. But the AC needed only 17. This means that with a little increase in AC you have the same result as if you increased HP a lot more. (OK nothing new;) but I am going to run other cases too.) Does anyone has made similar thoughts, calculations or run many times the same battle over and over? (Ideas for probabilities and computer sinmulations would be great)
20102000 10-07-05, 09:18 AM	I did look at something similar awhile back, with level progression. As you rise in levels your hp go up, you # attacks go up, and your + to hit goes up. You can also increase your damage and AC. However even with Min/Maxing the rate of increase on AC and damage is slower. What this all means is that at higher levels AC can be irrelavent. If your AC is 20, and a monsters to hit is +20/+15/+10/+5 its chance to hit is 95%, 75%, 50% and 25%. Or 2.45 hits per round. A +1 to AC will reduce the hits per round by 0.2. While a +1 to damage with increase damage by 2.45 per round. So AC related to ,bonus hit chance is an important measure. And tends to decrease as you rise in levels. Also damage becomes more important. At lower levels you might not hit or be hit, so the damge is less imortant. While at higher levels, you get hit, so the damage + becomes more important. Going through all the figures helped me understand the usefulness of power attacks, and combat expertise, especially at higher levels.
Edymnion 10-07-05, 02:57 PM	Its pretty simple, IMO. You will never have a character with an AC by higher levels that stands even a chance of stopping every attack that comes his way (usually its only good for stopping last few hits in a full attack). Hence, hitpoints are a much bigger, and much more important buffer against death than AC is.
Dragonsblood 10-07-05, 03:14 PM	I think your calculations are a bit off....you're saying that the guy with 1hp and 17ac will have a better chance of beating the guy with 200hp and 10ac. I don't think so.
BladeDrinker 10-07-05, 11:55 PM	You also have to consider the fact that AC doesn't protect you from spells, breath weapons and the like. HP's do. One bag of caltrops and your 1 hp character would be screwed.