power attack advice?

[Particle_Man]

I have a 3.0 fighter with str: 20, who uses a +1/+1 orcish double ax. He has exotic weapon prof, w. focus, w. spec., and imp. crit. in this weapon. He also has ambidex, and two-weapon fighting. And power attack and cleave. He is 8th level, so has the 2nd iterative attack.

So does anyone have a formula or generator for how much I should power attack? (Either when using it as a double weapon or when using it as a two-handed weapon?)

 

[Malin Genie]

There are formulas - but it depends what you want to achieve. Do you want to achieve maximum average damage? That isn't always the best use of the Feat; for example if you are facing a group of 20hp enemies, you would want to maximise the chance of dealing a 21hp or better blow, not maximise average damage.

 

[Scion]

Personally, when faced with questions like this I tend towards, 'all power attack, all the time' sort of answers

But yes, there are formulas, even ones from 3.0 floating around.. hopefully someone will put up a link to their site with one.

 

[Diirk]

Crunching a few numbers, up until ac 25 two weapon fighting does more damage than 2hand fighting on average (assuming full attacks, and powerattacking with neither).

If you want to power attack, then using 2hand fighting with 3.0 power attack if you even power attack for 1 point, you will do less damage on average unless your opponent has 19ac or less.

Using 2 weapon fighting and 3.0 power attack, you will do less damage on average unless your opponent has 21ac or less

I think these numbers are right, power attack is no where near as effective as alot of people think, but people like big numbers when they hit things

 

[Geoff Watson]

Since you are using 3.0, don't power attack unless the enemy has a stupidly low AC (gelatinous cube, inanimate objects, etc). PA is just an extra cost to get Cleave, which is a great feat.

Geoff.

 

[Staffan]

First, mathematical stuff. Basically, what you want to do is to maximize the formula 0.05*(n-P)*(d+P), where N is number of d20 rolls that lead to a hit (i.e. if you need 15 to hit, n=6) without power attack, P is the amount of power attack, and d is your average damage without power attack. Since, in any given situation, n and d are constants, as is the 0.05 factor (for the d20), the problem is basically the same as "If drawing a rectangle with a predetermined sum of the sides, what is the best ratio of width to height in order to get maximum area?" The answer to that question is making a square - in other words, you want to get (n-P) as close as possible to (d+P). The value of P that gives the closest value is the "best" amount of power attack. If you have multiple attacks, use the average value of n.

Example: You're fighting something that you need a 3 to hit with your primary and off-hand attacks (and thus an 8 with your secondary). 3 gives an n of 18, and 8 gives n=13. The relevant n is thus (18+18+13)/3 = ~16. Your damage is 1d8+8 (well, +5 with the secondary, but let's ignore that for the moment), for an average of 12.5. Here we have n-d = 4, so split the difference and you'll see that the optimal amount of power attack is 2.

So, short version: Make sure (number of results that hit-PA) is as close as possible to (average damage+PA). That'll get you reasonably close.

 

[argo]

Forget generators. I usually recomend these two rules of thumb. They may not give you the peak mathamatical damage but they are quick to use in-game and produce prety good results.

Rule 1, always power attack for a value equal to PA = (your weapon focus feats) + (the enhancement bonus of your weapon) + (any situational modifier (for example if you are charging or flanking PA for an extra +2, if you are on high ground PA for an extra +1)).

So for your character that would be PA = 1(wpn focus) +1(magic) = 2

Rule 2, always power attack for 1 + (1 per five full points of BAB) + (Str mod above 20)

So for your character that would be PA = 1 +1(BAB of 8) +0(Str is not above 20) = 2

Or you could just go all power attack all the time

Hope that helps.

 

[cordell]

Staffan's advice is perfect, but if you don't like the math, here are some good/easier guidelines:

Your bonuses using the weapon as 2 handed: +15 hit, +18 damage and another attack at +10hit/+18dam.

Your bonuses using both sides of the weapon: +13hit/+16dam, +13hit/+13dam, and another at +8hit/+16dam.

How much should I power attack for?

1) If you find yourself in a round where only 1 attack is possible, for example if you have to move first. This is simple - make sure you hit naturally on a roll of "2". For example, if the creature is AC 15, you would power attack for 2 pts. Now you are +13hit/+20dam, and if you roll a 2, you hit. You always miss on a 1 anyway, so who cares? This is a no-brainer, always do it.

2) No matter how many attacks you get, if the creatures die with your minimum damage, then never use Power Attack. No brainer.

3) For two attacks or more, power attacking doesn't generally increase your average damage by much, if at all. If your lowest-bonus-attack hits on a 1, then go ahead and PA using rule #1. In your example, if you are flanking a creature with AC 10, then definitely power attack for 2 pts - you are not losing anything, another no-brainer.

4) Usually, the creature AC's are not so low that your secondary attacks are hitting on a 1. In this case, you can power attack using rule 1 based upon the bonus of your primary attack, and your average damage will increase slightly over time. Its only a slight increase because while increasing your damage on the primary shots, you are losing out slightly on the secondary shots. This is better used on 1 big creature being fought for more than 5 rounds.

5) If your highest bonus attack doesn't have enough bonus to hit on a 2, then never power attack.

6) Since you have Cleave, this has to be considered. For rules 1 2 and 3, the no-brainers, Cleave doesn't matter. You aren't losing anything. In rule 4, definitely use power attack to raise your primary attacks if doing so brings the damage past the cleave threshold. In rule 5, if you can raise your damage enough to kill the creatures in one shot, then you should power attack. Even without great cleave, 1 extra attack from cleave offsets any extra misses on the secondary attacks.

Should I use both ends of my weapon (3 attacks) or use only one end (2 attacks)?

7) In general, with your bonuses, you want to take as many attacks as possible against creatures with low HP and low AC. If faced with 1 opponent, with a tougher AC (above 25 in your case, as Diirk said), then you should use only 2 attacks, not 3.

Hope that info helps...

 

[Patlin]

5) If your highest bonus attack doesn't have enough bonus to hit on a 2, then never power attack.

But if you can only hit on a 20 anyway, power attack full.

Also, lots of tricks can help out power attack. If you are can get Deep Impact, you can use it to make your second attack an easy hit... meaning power attack suddenly helps both of your attacks. True Strike is another natural synergy with power attack.

 

[Shadeus]

At 8th-level, it's not too huge a concern. Once you hit 11 and above and get that 3rd attack, it starts to matter a lot more. As a general rule, I try to go for a 75% chance to hit on the first attack. Or if I'm not sure of the AC, I approximate and guess its AC 20 (or whatever and calculate based on that. I figure a roll of a 6 to better to hit is fairly like and then is an 11 or better for that second attack. That's how I guage how strong a PA to use.

Oh, and if I just have no clue....I'll someone power attack to get nice multiples of 5 for each math. So if with all your bonuses you have a +23 to hit on that first attack, do a PA +3 and knock it down to 20. There's no science to that, it's just convenient.