Pathfinder, Help me calculate my chances to hit with 4d20+5 vs. 2d20+7

[Dimcair]

I apologize before hand. typing this on a phone and my fingers are just too big fore those...

hello everybody. i'd like to ask for some help in deciding when it is worth rolling 4d20 +5 and when rolling only 2d20s+7 is better. I am also very interested how a +1 to both modifiers (5and7)would change the statistics

some important variables:
the attack rolls are for thrown weapons, so only a 20 is a natural hit
the attack rolls will be made against targets who are flat footed (no dex mod to ac)

which brings me to AC
here i am very unsure. The character will be lvl 5 and spend some time in waterdeep (if that helps). Is there a good average to be used? 10+average armor? 15 maybe? 16? use any number you see fit. maybe a average number for medium difficulty encounters and one for high difficulty ones?

I am absolutely no use when it comes to math, especially not if it comes to statistics/probabillity, so dont expect me to understand any calculation formulas, but i would still be interested to see some.

I know this is some work, but maybe some of you guys are bored or can link me to a similar discussion.


greetz,

Dimcair

[Spore]

a)1d20 + 7 is averaging out in 17,5.
b)1d20 + 5 is averaging out in 15,5.

So you have 50% to miss an AC of 17.5 (and 15.5) respectively. However, since 4 attacks hit double as hard (assumption) as 2 attacks, your hit chance should be double that of the 2 attacks to get more damage.

a) To hit AC 23, you need to roll a 14 (20% hit chance).
b) To hit AC 23, you need to roll a 16 (10% hit chance).

Long story short, beginning at FF AC 23, you should consider switching off TWF. (If it IS TWF, maybe AC 22, since your offhand only has 1/2 Str bonus anyways). Also, these are weak attack bonusses for level 5, consider magical weapons and weapon foci to buff that.

[Dimcair]

Thanks for helping out sporeegg. And when I thought about it it didnt came to mind that one could just use the average roll of a d20+x (facepalm)


However, since 4 attacks hit double as hard (assumption) as 2 attacks, your hit chance should be double that of the 2 attacks to get more damage.




Could you explain that to me? I am not sure how the chance to hit is increased by 50% by more dmg potential. Do you mean the average damage increases?

As for Offhand dmg or strength modifiers, dont worry. i have a strength of 10 (put 16 in con). the dmg will come from sneak attack 3d8 (knife master)

the more i hit the more dmg it will be, but as always if i dont then it will be 0 dmg


/edit. to explain a bit more
a) is made at a -2 penality TWF
b) is made at a -4 penality TWF+Rapid Shot

bab is 3+5dex +1 PBShot so 9

weaponfocus daggers will come at lvl 6, but for weapons it will depend on our mercyless DM (<3) and my ability to have a lot of daggers enchanted, since they will be the ammunition. Any ideas for that? Whats the cheapest? Maybe get weapon oil or smth?

[gartius]

question-how does TWF +rapid shot get you four attacks-by my reckoning it only gets you three.

TWF
Benefit: Your penalties on attack rolls for fighting with two weapons are reduced. The penalty for your primary hand lessens by 2 and the one for your off hand lessens by 6. See Two-Weapon Fighting.

Normal: If you wield a second weapon in your off hand, you can get one extra attack per round with that weapon. When fighting in this way you suffer a –6 penalty with your regular attack or attacks with your primary hand and a –10 penalty to the attack with your off hand. If your off-hand weapon is light, the penalties are reduced by 2 each. An unarmed strike is always considered light.

Rapid shot
When making a full-attack action with a ranged weapon, you can fire one additional time this round. All of your attack rolls take a –2 penalty when using Rapid Shot.


so full attack action gives you 2 attacks from rapid shot then one extra attack from TWF

[Mystral]

Maybe he flurrys?

[Dimcair]

Nah gartius is right. You can't pull it off. Poor reading of my part, still learning. Thankfull for the calculation approach do. not that important for a game but it is still nice to know of what you are doing is completely stupid or not.

ashamed:eek: ,
dimcair

[Adverb]

This might be helpful to you:

If your goal is to maximize expected hits, and you have the option of making one attack at +X, or two at X-2, or three at X-4, you can grind out all the probabilities and look at them and it turns out there's a simple rule.

If you need to roll 13-17 on the die to hit, take two attacks at X-2.

If you hit easier than a 13, you might as well spam attacks at X-4. If you need an 18 or better, fishing for natural 20s isn't a bad idea and spam helps with that too.

The math changes if ammo is expensive or if you're trying to decide between TWF or THF, but if your decision is just "do I use Flurry of Blows or not", the above applies. Having a secondary attack at -5 changes the math, but doesn't change the 13-17 rule.

[Dimcair]

Puh, so would you still feel its worth taking the feats to be able to spam 3 attacks at -4? namely pbs (which is a good feat anyways because the +1 to hit) and then it is actually just rapid shot.


edit: oh i think we posted our last posts at the same time. flurry of blows wont apply.

[Adverb]

Short answer: No, I wouldn't.

The math was done for someone who was building a monk with Snap Kick. Monks get Flurry by default, and Snap Kick offers some unique things that Flurry doesn't. In the 13-17 range where 2/-2 is best, it turns out your expected hits for 1/-0 or 3/-4 are about the same, close enough that the tiebreaker might be the lower damage from Snap Kick. If you're hitting on low rolls, this fight is probably over anyway.

So in hard-enough-to-be-exciting play, more than one extra swing doesn't help you any, and makes you take more time at the table rolling dice and doing math. I like rolling dice, but the satisfying part to me is making decisions, so I'd use my feats on things which give me new options rather than cranking up the intensity on existing options.

That said, a lot of people really get a lot of their fun out of rolling dice, and if you're one of those, you should do this thing which would let you roll more dice, and on the rounds where you have a one-round +6 to hit you'll be a demigod of destruction.

[Dimcair]

Thank you =), then it stays for flavor and i might exchange it for another feat at lvl 6 since we had our first session yesterday


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