Elven Accuracy wording vs maths - sanity check

[UngeheuerLich]

No. That is not how rerolling works. Look at advantage disadvantage. Relevant quotes:

"When a creature you can see hits you with an attack roll, you can use your reaction to force that creature to reroll. Once you use this ability, you can’t use it again until you roll initiative at the start of combat or until you finish a short or long rest."
From xanathar's guide

"When you have advantage or disadvantage and something in the game, such as the halfling's Lucky trait, lets you reroll or replace the d20, you can reroll or replace only one of the dice. You choose which one. For example, if a halfling has advantage or disadvantage on an ability check and rolls a 1 and a 13, the halfling could use the Lucky trait to reroll the 1."
From the PHB

As I read the licky trait of the halfling again it gets a bit less clear. The lucky trait explicitely mentions the d20, the second chance feat refers to the attack roll. It was an edge case anyway and you could rule both ways I guess.

 

[UngeheuerLich]

Numerically, it's the same as just having super advantage. It just changes when you get that super advantage.

https://anydice.com/program/12dd3

Turning what an enemy though was disadvantage (avg roll of 7) on you to super advantage (avg roll of 15) is a large effect.

Sorry. You didn't understand. You won't pick the best of 3 dice but you reroll one from disadvantage and still take the lower. It is different from the in my opinion botched wording where you pick any of the three dice you want. But maybe I was not clear enough.
It should not be the equivalent to best of 3 but instead the equivalent of the middle one of three instead of the worst of two.
Example: you roll 13 and 2. You reroll the 2 to a 19. You now take the 13 as it is the lower of 13 and 19.
With accuracy on advantage it would be 19 as you pick the higher of both.

I now clicked on your link and found your error. The last line needs to be lowest of A and B
Note that I didn't have to click the link to know there was an error.

 

[Yunru]

No. That is not how rerolling works. Look at advantage disadvantage. Relevant quotes:

"When a creature you can see hits you with an attack roll, you can use your reaction to force that creature to reroll. Once you use this ability, you can’t use it again until you roll initiative at the start of combat or until you finish a short or long rest."
From xanathar's guide

"When you have advantage or disadvantage and something in the game, such as the halfling's Lucky trait, lets you reroll or replace the d20, you can reroll or replace only one of the dice. You choose which one. For example, if a halfling has advantage or disadvantage on an ability check and rolls a 1 and a 13, the halfling could use the Lucky trait to reroll the 1."
From the PHB

As I read the licky trait of the halfling again it gets a bit less clear. The lucky trait explicitely mentions the d20, the second chance feat refers to the attack roll. It was an edge case anyway and you could rule both ways I guess.

But that is how it works in effect. You roll two dice, then reroll the lower. It's functionally identical to rolling 3 dice.
EDIT: For advantage that is. Elven Accuracy does literally nothing for disadvantage.

 

[MarkB]

No. That is not how rerolling works. Look at advantage disadvantage. Relevant quotes:

"When a creature you can see hits you with an attack roll, you can use your reaction to force that creature to reroll. Once you use this ability, you can’t use it again until you roll initiative at the start of combat or until you finish a short or long rest."
From xanathar's guide

"When you have advantage or disadvantage and something in the game, such as the halfling's Lucky trait, lets you reroll or replace the d20, you can reroll or replace only one of the dice. You choose which one. For example, if a halfling has advantage or disadvantage on an ability check and rolls a 1 and a 13, the halfling could use the Lucky trait to reroll the 1."
From the PHB

As I read the licky trait of the halfling again it gets a bit less clear. The lucky trait explicitely mentions the d20, the second chance feat refers to the attack roll. It was an edge case anyway and you could rule both ways I guess.

Also, the PHB quote is about when something lets you reroll a d20, rather than when it forces you to do so. By your ruling, if I rolled a 16 and an 18 on my attack with advantage, and you used Second Chance to force me to reroll my attack, I could re-roll the 18, get a 1, and yet still keep the 16 because it was now the higher result. I don't think that's the intended result.

 

[UngeheuerLich]

But that is how it works in effect. You roll two dice, then reroll the lower. It's functionally identical to rolling 3 dice.

Please read the whole post.
The edge case is one roll replaced by one ability. The other one by the next. If you had 3 dice, one would have left unchanged.
Assume: 2 dice are rolled: one is 13, one 17. You assume the 17 would hit anyway. You try to get a crit and reroll the 13 and just get a 1 and miss. Your rolls are now 1 and 17. A different effect makes you reroll the 13 also and also get a 1. You now have 1 and 1.
If you initially started with 3 dice, you would have gotten 13, 17 and 1. The other trait has you reroll the 17. You get a 1 and your roll is now 13, 1, 1.
Your 13 might still hit.
How big are the chances to ntice the difference. About 0%. Is there a difference? Yes, but only when another effect also makes or allows you to reroll the other d20 die.

 

[UngeheuerLich]

Also, the PHB quote is about when something lets you reroll a d20, rather than when it forces you to do so. By your ruling, if I rolled a 16 and an 18 on my attack with advantage, and you used Second Chance to force me to reroll my attack, I could re-roll the 18, get a 1, and yet still keep the 16 because it was now the higher result. I don't think that's the intended result.

Probably. But probably it is. I wouldn't challenge your ruling after reading the PHB entries again however.

 

[Yunru]

Please read the whole post.
The edge case is one roll replaced by one ability. The other one by the next. If you had 3 dice, one would have left unchanged.
Assume: 2 dice are rolled: one is 13, one 17. You assume the 17 would hit anyway. You try to get a crit and reroll the 13 and just get a 1 and miss. Your rolls are now 1 and 17. A different effect makes you reroll the 13 also and also get a 1. You now have 1 and 1.
If you initially started with 3 dice, you would have gotten 13, 17 and 1. The other trait has you reroll the 17. You get a 1 and your roll is now 13, 1, 1.
Your 13 might still hit.
How big are the chances to ntice the difference. About 0%. Is there a difference? Yes, but only when another effect also makes or allows you to reroll the other d20 die.

But you just quoted that you get to choose which to reroll. So you reroll the 13 and get a 1. You have to reroll due to an outside effect, so you reroll the 1 again.

 

[UngeheuerLich]

But you just quoted that you get to choose which to reroll. So you reroll the 13 and get a 1. You have to reroll due to an outside effect, so you reroll the 1 again.

Stupid me. Yes. YOU chose and reroll the same again. I thought the you referred to the one making you reroll. Actually the text seems to only refer to yourself allowing a reroll, not someone forcing you to do so. Hmm...
But I was wrong. Sorry.

 

[Tyrfingr]

Sorry. You didn't understand. You won't pick the best of 3 dice but you reroll one from disadvantage and still take the lower. It is different from the in my opinion botched wording where you pick any of the three dice you want. But maybe I was not clear enough.
It should not be the equivalent to best of 3 but instead the equivalent of the middle one of three instead of the worst of two.
Example: you roll 13 and 2. You reroll the 2 to a 19. You now take the 13 as it is the lower of 13 and 19.
With accuracy on advantage it would be 19 as you pick the higher of both.

I now clicked on your link and found your error. The last line needs to be lowest of A and B
Note that I didn't have to click the link to know there was an error.

So, basically you are just erasing disadvantage with Elven Accuracy. The middle of 3 dice is the same mean result with a slightly smaller standard deviation.

With that thought, if you have a situation where Advantage, Disadvantage both exist and Elven Accuracy applies, in what order would you apply the effects? If Advantage and Disadvantage cancel each out is Elven Accuracy just wasted? Or would you let the Elven Accuracy cancel out the Disadvantage and end up giving the character advantage again?

 

[UngeheuerLich]

So, basically you are just erasing disadvantage with Elven Accuracy. The middle of 3 dice is the same mean result with a slightly smaller standard deviation.

With that thought, if you have a situation where Advantage, Disadvantage both exist and Elven Accuracy applies, in what order would you apply the effects? If Advantage and Disadvantage cancel each out is Elven Accuracy just wasted? Or would you let the Elven Accuracy cancel out the Disadvantage and end up giving the character advantage again?

Good question. I need to think about that. Now that you mention it, I am not sue anymore that my idea was good to begin with. Sometimes lower deviation is indeed advantageous. Maybe some ability that just allows you to reroll an attack with a d12 or a d10 in addition to any die you roll, advantage, disadvantage or not might be a better ability. That way you have an extra chance to hit with a lower chance of succeess. Maybe you might chose to take the new result or stay with the old one.