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Message: <blockquote data-quote="Bacon Bits" data-source="post: 7045775" data-attributes="member: 6777737">Absolutely.First, your math is wrong:[code](2 x Attack Bonus - Average Damage per Hit + 32) / 2[/code]Attack Bonus = 11Average damage per hit = 12.35[code](2 * 11 - 12.35 + 32) / 2 = (22 - 12.35 + 32) / 2 = 41.65 / 2 = 20.825 --> AC 20[/code]Don't forget your PEDMAS!Second, where does the formula come from?Step 1.  Define the chance to hit.[code](21 + Attack Bonus - Target AC) / 20[/code]We use 21 instead of 20 because you hit on a tie.  If I have a +11 attack bonus and I roll an 11, I hit AC 22, right?  And 11-20 is 50% of a d20.  So we'd expect this formula to result in 0.50 with those values:[code](21 + 11 - 22) / 20 = 0.50[/code]And so it is.Step 2.  Define the average damage per attack prorated for the chance to hit.[code]Average Damage on Hit * (21 + Attack Bonus - Target AC) / 20[/code]So, if you deal 12.35 damage per hit, have a +11 attack bonus, and are attacking a target with AC 22:[code]12.35 * (21 + 11 - 22) / 20 = 12.35 * 0.50 = 6.175[/code]Step 3.  Define the prorated average damage of power attacking using the terms we have when we don't power attack.In other words, Attack Bonus is still 11 and Average Damage is still 12.35.[code](Average Damage on Hit + 10) * (21 + Attack Bonus - 5 - Target AC) / 20[/code]Or, more simply:[code](Average Damage on Hit + 10) * (16 + Attack Bonus - Target AC) / 20[/code]So you were power attacking, you'd do this:[code](12.35 + 10) * (16 + 11 - 22) / 20 = 22.35 * 0.25 = 5.5875[/code]Step 4.  Put Step 2 and Step 3 together.  We want to know when the prorated average damage for power attacking (Step 3) is greater than the prorated average damage normally (Step 2):[code](Average Damage on Hit + 10) * (16 + Attack Bonus - Target AC) / 20 > Average Damage on Hit * (21 + Attack Bonus - Target AC) / 20[/code]Step 5.  Solve for Target AC.Now, I don't know about you, but I'm really freaking lazy.  I don't want to do algebra myself.[code]Let x = Target ACLet a = Attack BonusLet d = Average damage on hit(d + 10) * (16 + a - x) / 20 > d * (21 + a - x) / 20[/code]Now, <a href="http://www.wolframalpha.com/input/?i=(d+%2B+10)+*+(16+%2B+a+-+x)+%2F+20+%3E+d+*+(21+%2B+a+-+x)+%2F+20" target="_blank">Wolfram Alpha will solve it for us</a>.  Follow that link and scroll down to "Solution," and you will see:[code]x < 1/2 * (2a - d + 32)[/code]Or:[code]Target AC < 1/2 * (2 * Attack bonus - Average damage on hit + 32)[/code]So, this value gives us the point at which above formula changes:[code]1/2 * (2 * Attack bonus - Average damage on hit + 32)[/code]That's likely to be a fractional value, however, so we can round down and be confident that for AC will benefit power attack:[code]Maximum AC for power attack = Floor [ 1/2 * (2 * Attack bonus - Average damage on hit + 32) ][/code]</blockquote>

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