The Mechanical Impact of -5/+10

Yunru · Jan 11, 2019

Here's a breakdown of how using -5/+10 affects average damage, when you deal an average damage of X, and need to roll a minimum of Y on the die to hit (N.B. I'll be going lower than 2 because while the chance for success without -5/+10 ceases to change, the chance for success with it continues to change). The value you get is the increase, so a negative means -5/+10 does less damage.

Y	-3	-2	-1	0	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20
Dmg Diff	9.5	9-0.05X	8.5-0.1X	8-0.15X	7.5-0.2X	7-0.25X	6.5-0.25X	6-0.25X	5.5-0.25X	5-0.25X	4.5-0.25X	4-0.25X	3.5-0.25X	3-0.25X	2.5-0.25X	2-0.25X	1.5-0.25X	1-0.25X	0.5-0.25X	0.5-0.2X	0.5-0.15X	0.5-0.1X	0.5-0.05X	0.5

FrogReaver · Jan 12, 2019

The impact of -5/+10 depends on both attack and damage before the feat is applied.

If you hit on 11+ but only do 1 damage on a hit then -5/+10 increases your DPR despite the chart above showing it does less.

Edit: nevermind apparently the forum shows dmg as one line and dmg difference as another. The -x part appears in the dmg diff line so it looked like 3 separate things you were chatting.

Yunru · Jan 12, 2019

FrogReaver said:
The impact of -5/+10 depends on both attack and damage before the feat is applied.

If you hit on 11+ but only do 1 damage on a hit then -5/+10 increases your DPR despite the chart above showing it does less.

Edit: nevermind apparently the forum shows dmg as one line and dmg difference as another. The -x part appears in the dmg diff line so it looked like 3 separate things you were chatting.

No? You're ignoring the -5 part of -5/+10. 50% of 1 is 0.5, 25% of 11 is 2.75. Difference of 2.25.

Edit: I gotta stop replying after you've edited but before I've refreshed. That or read what I quote.

generic · Jan 12, 2019

Yunru said:
Here's a breakdown of how using -5/+10 affects average damage, when you deal an average damage of X, and need to roll a minimum of Y on the die to hit (N.B. I'll be going lower than 2 because while the chance for success without -5/+10 ceases to change, the chance for success with it continues to change). The value you get is the increase, so a negative means -5/+10 does less damage.

Y
-3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Dmg Diff
9.5 9-0.05X 8.5-0.1X 8-0.15X 7.5-0.2X 7-0.25X 6.5-0.25X 6-0.25X 5.5-0.25X 5-0.25X 4.5-0.25X 4-0.25X 3.5-0.25X 3-0.25X 2.5-0.25X 2-0.25X 1.5-0.25X 1-0.25X 0.5-0.25X 0.5-0.2X 0.5-0.15X 0.5-0.1X 0.5-0.05X 0.5

Thanks for this [MENTION=6780961]Yunru[/MENTION], I was planning on doing an analysis of all of the static bonuses in 5e.

5ekyu · Jan 12, 2019

Thanks... a lot of the in-play value comes down to this but also two factors that add to it:
GM - The types of foes and situations - that affects the base Ac vs to-hit factors.
GM & Players - The frequency with which advantage and disadvantage apply to strikes as they shift the odds a bit in each direction.

While obviously with perfect knowledge a 5/10 character wont ever take the negative choice, in play its not always known and more to the point, the greater the number of times the 5/10 is the worst choice diminishes its overall value - as compared to more universally applicable "use every time i can" options like say ASI or other feats.

Shiroiken · Jan 12, 2019

5ekyu said:
Thanks... a lot of the in-play value comes down to this but also two factors that add to it:
GM - The types of foes and situations - that affects the base Ac vs to-hit factors.
GM & Players - The frequency with which advantage and disadvantage apply to strikes as they shift the odds a bit in each direction.

While obviously with perfect knowledge a 5/10 character wont ever take the negative choice, in play its not always known and more to the point, the greater the number of times the 5/10 is the worst choice diminishes its overall value - as compared to more universally applicable "use every time i can" options like say ASI or other feats.

I've found that unless the player knows they have advantage, they tend to not use it on the first attack of the combat. Getting an idea of the target's AC allows for better assessment of the risk/reward. With advantage, even against an unknown AC, players tend to jump on the -5/+10, because it seems more often than not the advantage assures them success.

5ekyu · Jan 12, 2019

Shiroiken said:
I've found that unless the player knows they have advantage, they tend to not use it on the first attack of the combat. Getting an idea of the target's AC allows for better assessment of the risk/reward. With advantage, even against an unknown AC, players tend to jump on the -5/+10, because it seems more often than not the advantage assures them success.

That sounds reasonable as a rough means of assessment and one that throws a lot to the campaign and circumstance for "how much is it worth vs ASI" (or versus feats thst give you less circumstantially limited gains) as well as "who will it be good against?"

Many times I see groups getting advantage a lot more often against less dangerous foes - ones relatively straightforward. Meanwhile, more dangerous and cagey adversaries often have more ways to avoid giving out advantage (or generating disadvantage to counter it) and so features that depend on having advantage often turn up useless whren it could matter the most.

Stalker0 · Jan 12, 2019

Let try an example to ensure we are all reading the table right. So lets assume you need a 5 or better to hit, and do an average of 10 dmg before the feat is applied.

So the formula is 5.5 - .25X. So that 5.5 - .25 * 10 = 5.5 - 2.5 = 3. So this means that my average damage increases by 3.

Now where I'm confused is when you defined average damage. So for example if I had a greatsword doing 2d6 + 3, that's an average damage of 10. Is that X, or is the damage times the current accuracy meant to be X?

Is this table also factoring in crits? I don't see how it could since your not accounting for damage dice anywhere.

Yunru · Jan 12, 2019

Stalker0 said:
Let try an example to ensure we are all reading the table right. So lets assume you need a 5 or better to hit, and do an average of 10 dmg before the feat is applied.

So the formula is 5.5 - .25X. So that 5.5 - .25 * 10 = 5.5 - 2.5 = 3. So this means that my average damage increases by 3.

Now where I'm confused is when you defined average damage. So for example if I had a greatsword doing 2d6 + 3, that's an average damage of 10. Is that X, or is the damage times the current accuracy meant to be X?

Is this table also factoring in crits? I don't see how it could since your not accounting for damage dice anywhere.

X is just the damage the weapon does when it hits, accuracy is factored into the table itself.

The table doesn't factor in criticals, although it shouldn't change anything since both sides get increased by the same amount (5% of the average damage of the added dice) at all times.

FrogReaver · Jan 12, 2019

Yunru said:
No? You're ignoring the -5 part of -5/+10. 50% of 1 is 0.5, 25% of 11 is 2.25. Difference of 1.75.

Edit: I gotta stop replying after you've edited but before I've refreshed. That or read what I quote.

FYI: The chart is much more readable on the desktop version than on the mobile version