D&D 4E The math behind power attack and why it needs to be redone in 4e

[Doug McCrae]

@ Damage Reduction matters posts: It only matters when you go to apply the actual damage. Still, that doesn't change power attack being subpar. If I use a magic weapon with a +3 damage bonus and I have a +2 bonus from a buff spell, effectively I am at +5 to damage, just as I would be with power attack if I took a -5 penalty to hit.

What about where the damage on power attack dips down? In those cases power attack hurts you getting over DR. My point is you can compare average damage before DR in every case (weapon damage, spell damage, power attack modified damage, magic weapon damage) it is all damage, and they all get compared to DR the same. Now if power attack actually said, it ignores DR 5 or DR 10, then it would matter. And yes, technically, power attack affects average damage..but the point isn't to compare it to DR, the point is to look at the raw damage. I can have 2 point strength buff and get more out of that then the power attack feat with a one handed weapon. In all of these examples, DR is a unrelated factor to proving power attack's value. The ONLY time DR matters in this study and power attack is a benefit is if you have enough to hit to take a penalty and still hit on a 2+ on your roll.

Those numbers quoted in the tables above are reduced because they are multiplied by the percentage chance to hit. You can't use those figures to work out the actual damage delivered to a monster with DR because DR is only subtracted from blows that hit.

For example say I do 2d6+13 damage, for an average of 20 per hit, but I only have a 50% chance of hitting. That's an average damage per round of 10 (20 * 50%). Let's say an opponent has DR5. If we simply subtracted that DR from the ADPR that would give a final ADPR of 5. But that number would be wrong, because that DR5 isn't coming off blows doing an average of 10 points of damage. It's really coming off blows that do an average of 20 points of damage. So the true ADPR would be ((20-5) * 50%) = 7.5.

You have to take the DR off the damage first, then apply the percentage chance of hitting, to get the true ADPR.

 

[Najo]

I'm not sure what you're trying to say here. A defender's DR effectively moves the attacker's average damage down, and we know that power attack is most useful when the attacker's average damage is low.

I am saying that regardless if my damage is low or not, if I take a penalty to my to hit it doesn't matter, I am missing more often now. Power attack doesn't help against DR unless you can keep your to hit good enough and get your damage boosted above the DR. Power Attack is deceptive becuase of the to hit penalty first and foremost. Your basically throwing your attacks away.

 

[Najo]

My fix for power attack:

* Rename it "Tactician"
* Make its prerequisite Int 13

Done!

Now it's works as a careful math exercise that benefits high attack over damage. The careful planning with it represents the feel of the new fluff of the feat. And it is more useful for high to-hit, low damage fighters. High Int/Dex planner archetypes.

Except that isn't what a tactician is. Aimed Strike or Precision Strike is more accurate.

 

[Someone]

It has always bothered me a little bit that the broadest statistical advantage of a feat that seems intended to reflect somewhat-wilder, more powerful swings would most effectively be employed by characters wielding smaller, lighter weapons that don't deal a significant amount of damage without it. Interestingly enough, I can't think of a single player I've had in the last seven years who wielded knives and rapiers and such who turned to Power Attack as a low- to mid-level feat selection. They tend to go right to the feats that seem to more appropriately represent their specific weapon selections, while the greatsword and greataxe wielders have always been quick to snatch it up.

As for the effectiveness of the feat... predictably, mileage has certainly varied.

That could be partially because finesse fighters have a greater range of feats that benefit them or are thematically appropiate (two weapon fighting tree, spring attack, etc) and big weapon users have less, and one of the most used ones (the Cleave tree) starts with Power attack. Still, the feat designer's point that it doesn't do what it was meant to do, namely help big weapon users, it's true: it helps light weapon users more, or did in 3.0. That doesn't mean it's a bad feat: just that it doesnt work as intended. Possibly, the best way to "fix" it, and notice the inverted commas, would be to alow the user to deal extra weapon damage dice for a fixed penalty. That way, the bigger the weapon the better the feat would work.
That said, I never found the feat bad, under or overpowered, once I did the math and realized how should it be used. It's still great when attacking unattended items, doors, etc, or as said, when you really need to deal a lot of damage very quickly and a lesser amount of damage, no matter how accurate, would not work.

 

[mmadsen]

I am saying that regardless if my damage is low or not, if I take a penalty to my to hit it doesn't matter, I am missing more often now. Power attack doesn't help against DR unless you can keep your to hit good enough and get your damage boosted above the DR. Power Attack is deceptive becuase of the to hit penalty first and foremost. Your basically throwing your attacks away.

Najo, we have a well-defined quantitative method of determining how much power-attacking helps or hurts. I'm not sure why you're abandoning it now.

An attacker who does, say, 1d8+5 damage (9.5 average), would not want to power-attack unless he would ordinarily hit on a 10 or higher. Against DR 5, he would want to power-attack even if he would ordinarily hit only on a 15 or higher.

 

[Najo]

Those numbers quoted in the tables above are reduced because they are multiplied by the percentage chance to hit. You can't use those figures to work out the actual damage delivered to a monster with DR because DR is only subtracted from blows that hit.

For example say I do 2d6+13 damage, for an average of 20 per hit, but I only have a 50% chance of hitting. That's an average damage per round of 10 (20 * 50%). Let's say an opponent has DR5. If we simply subtracted that DR from the ADPR that would give a final ADPR of 5. But that number would be wrong, because that DR5 isn't coming off blows doing an average of 10 points of damage. It's really coming off blows that do an average of 20 points of damage. So the true ADPR would be ((20-5) * 50%) = 7.5.

You have to take the DR off the damage first, then apply the percentage chance of hitting, to get the true ADPR.

I agree, but most creatures don't have DR and it is possible to bypass them with the right weapons. So DR does not affect power attack as frequently or severly as some people feel. Also, you don't need to subtract the DR before applying the hit chance. You can apply the miss chance to the DR and then subtract it from the average damage and get the same result.

 

[Wolfwood2]

Of course, the real benefit to Power Attack is when you have ways to multiply your damage.

Actual Play example.

I have a 9th level paladin with Power Attack that I play in a bi-weekly game. Last session we were in an arena-type combat with plenty of room and multiple buffing spells. My PC was mounted and using a lance two-handed. On a charge attack, every point of to-hit bonus he sacrificed brought him 4 points of damage. When I used a spell, that jumped to 6 points of damage.

Becuase of the multiple buff spells, he was at +22 to hit on a mounted charge. By sacrificing 4 points on power attack, I turned 2d8+16 damage into 2d8+32 damage.

Did power attack benefit my in that situation? Oh yes it did.

 

[Najo]

Najo, we have a well-defined quantitative method of determining how much power-attacking helps or hurts. I'm not sure why you're abandoning it now.

An attacker who does, say, 1d8+5 damage (9.5 average), would not want to power-attack unless he would ordinarily hit on a 10 or higher. Against DR 5, he would want to power-attack even if he would ordinarily hit only on a 15 or higher.

I am not abandoning it or you! Just trying to drive home and defend that DR is not as much of a consideration to average damage in determing the worth of power attack and its effect. DR is a seperate issue, as you've shown, that basically tells you how much more of a minus you need to be willing to take. Thus, power attack is only decent with excessive and expendable to hit bonses that over take a creatures's DR if it has it.

 

[drothgery]

Of course, the real benefit to Power Attack is when you have ways to multiply your damage.

Actual Play example.

[...]

Becuase of the multiple buff spells, he was at +22 to hit on a mounted charge. By sacrificing 4 points on power attack, I turned 2d8+16 damage into 2d8+32 damage.

Did power attack benefit my in that situation? Oh yes it did.

But if you had missed by one point (or four), then Power Attack would have hurt you. And examples like this are why people overestimate the benefit of PA; you usually remember the times when it worked and did a ton of damage, but not the times you just barely whiffed and so did none.

 

[s-dub]

Power attack is a feat that allows a player great advantages with certain builds or certain situations. In this it's just like any other feat.

Part 1: Body Building

Build #1.

Frenzied Berzerker. All PA, all the time =P

Build #2.

Gish with truestrike

Build #3.

Anything with 6 or more natural attacks (Dire Octopus comes to mind, as does most age categories of dragon)

Build #4.

Any melee psionic build with Deep impact.

Part 2: Situational Ethics

Situation 1:

Attacking an object; almost all objects have low AC and high hardness

Situation 2:

Incorporeal Creatures; normally have low AC and very high manueverability

Situation 3:

Mooks.