Say you have advantage on a d20 test and fail with both rolls. If you have Heroic Inspiration, then you can expend it to reroll once and must use the new roll. What if you have a means to give yourself advantage on a roll (e.g., Tides of Chaos)? Can that be applied to give you advantage on the Heroic Inspiration reroll?
It's not possible to use Advantage (EDIT: or Disadvantage) in the Heroic Inspiration reroll:
For example, if you have Heroic Inspiration (see the sidebar) and roll a 3 and an 18 on an ability check that has Advantage or Disadvantage, you could expend your Heroic Inspiration to reroll one of those dice, not both of them.
If you have Heroic Inspiration, you can expend it to reroll any die immediately after rolling it, and you must use the new roll.
That's the question: whether advantage can be applied to a heroic inspiration reroll. Both excerpts you provide highlight the "one reroll." But it's unclear to me whether advantage can be applied to that reroll (which I understand is still a roll for d20 test).
That's the question: whether advantage can be applied to a heroic inspiration reroll. Both excerpts you provide highlight the "one reroll." But it's unclear to me whether advantage can be applied to that reroll (which I understand is still a roll for d20 test).
You are re-rolling one die, not making a brand new D20 test and thus you only get to re-roll that one die.
Say you have advantage on a d20 test and fail with both rolls. If you have Heroic Inspiration, then you can expend it to reroll once and must use the new roll. What if you have a means to give yourself advantage on a roll (e.g., Tides of Chaos)? Can that be applied to give you advantage on the Heroic Inspiration reroll?
No, I wouldn’t allow that because, HI is used to replace 1 failed roll. It’s not a total do over. Also in my opinion it would make HI way over powered. Not something I would do or would allow. Also RAW “reroll 1 failed d20 test”, not reverse time and total do over.
It's worth pointing out that the "reroll one die" limitation also applies to things like damage rolls. For instance if you cast Shatter, which does 3d8 damage, and get a 1, a 1, and an 8, you can use Heroic Inspiration to reroll one of those 1s, but not both of them.
What if you have advantage, say roll a 14 and 8. You decide to use HI to reroll the 8 and get a 1. Do you have to take the 1?
No, re-rolls from Heroic Inspiration are done before success/failure is determined. So first you had 14/8 to choose from but after the re-roll you instead have 14/1 to choose from but you still pick the highest and that would be the 14 in both cases.
Exactly. That's what the rule says (green text added by me):
For example, if you have Heroic Inspiration (see the sidebar) and roll a 314 and 188 on an ability check that has Advantage or Disadvantage, you could expend your Heroic Inspiration to reroll one of those dice (e.g., reroll the 8 and get a 1), not both of them.
Nope, since you must use the new roll, you must reroll both, since you can't use the lower roll if the new lower roll is lower due to Advantage, and you can't use the higher roll if the reroll is higher with the Disadvantage... Advantage says you use the Higher Roll, Disadvantage says you must use the lower roll, Heroic Inspiration says you use the new roll, for both to work, you MUST reroll both so you are guaranteed the new roll is the correct roll for Advantage or Disadvantage... Anyone who says Otherwise didn't read the wording of all three.
"You must use the new roll" means the new roll is used in place of the roll you're re-rolling. It doesn't mean you must use it for the final outcome of the ability check, damage roll, etc.
For example, you're making a d20 test and roll an 11. You decide to use Heroic Inspiration and re-roll it, rolling a 6. You can't choose to keep the original 11, you must use the 6 as the result of that dice roll.
However, let's say you had advantage on that same d20 test and rolled a 7 and a 12. You decide to Heroic Inspiration that 12 (for whatever reason) and roll instead a 4. "You must use the new roll" doesn't mean "Even though you rolled a 4 and a 12, you must use the 4 ignoring the rules of advantage". It actually means "You cannot choose to keep the 12 instead of the re-rolled 4, you must take that 4." and then the rules for advantage apply and you use the 7.
You must USE, not must pick from the new roll and the other half of the old roll... If you must use the new roll, you MUST use the new roll, not any part of the old roll... the other die would be the old roll... ergo, vis a vi, the only way to do it is to reroll both, because no one would ever reroll the higher roll on advantage nor disadvantage rolls, since rerolling the lower roll always would benefit more, while if you roll both you are taking a risk of losing the benefit of better rolls.
Your example is invalid, because you would automatically never choose the 12... you would always choose the 7, hoping to get a 13+, making the 12 the lower roll, while with advantage you would roll the 7, also hoping for something much higher that the 12 so you get the higher roll... rolling both means you could get a 2 and a 3, both lower that then 7 and have to take the lower on disadvantage and the higher on advantage, which is still a 2 and a 3... not a 7 nor a 12 either way...
Only way to make sure it is advantage/disadvantage is to reroll both
When a roll has either Advantage or Disadvantage, roll a second d20 when you make the roll. Use the higher of the two rolls if you have Advantage, and use the lower roll if you have Disadvantage. For example, if you have Disadvantage and roll an 18 and a 3, use the 3. If you instead have Advantage and roll those numbers, use the 18.
Interactions with Rerolls
When you have Advantage or Disadvantage and something in the game lets you reroll or replace the d20, you can reroll or replace only one die, not both. You choose which one.
For example, if you have Heroic Inspiration (see the sidebar) and roll a 3 and an 18 on an ability check that has Advantage or Disadvantage, you could expend your Heroic Inspiration to reroll one of those dice, not both of them.
You must USE, not must pick from the new roll and the other half of the old roll... If you must use the new roll, you MUST use the new roll, not any part of the old roll... the other die would be the old roll... ergo, vis a vi, the only way to do it is to reroll both, because no one would ever reroll the higher roll on advantage nor disadvantage rolls, since rerolling the lower roll always would benefit more, while if you roll both you are taking a risk of losing the benefit of better rolls.
"You must use the new roll" very simply means you cannot choose to keep the old roll of that dice. It does not mean it must be used in the final determination of the overall d20 test.
Your example is invalid, because you would automatically never choose the 12... you would always choose the 7, hoping to get a 13+, making the 12 the lower roll, while with advantage you would roll the 7, also hoping for something much higher that the 12 so you get the higher roll... rolling both means you could get a 2 and a 3, both lower that then 7 and have to take the lower on disadvantage and the higher on advantage, which is still a 2 and a 3... not a 7 nor a 12 either way...
My example is not invalid because there's no rule forcing you to choose the worse dice. Yes, I'll concede, choosing the better dice is not a sensible choice, but it's still a valid one. You're projecting "This is not something I would ever choose to do" into "This is not something anyone ever would choose to do" and then projecting that onto "This is not something the rules allow you to do". That is invalid.
Only way to make sure it is advantage/disadvantage is to reroll both
When you have Advantage or Disadvantage and something in the game lets you reroll or replace the d20, you can reroll or replace only one die, not both. You choose which one.
For example, if you have Heroic Inspiration (see the sidebar) and roll a 3 and an 18 on an ability check that has Advantage or Disadvantage, you could expend your Heroic Inspiration to reroll one of those dice, not both of them.
You cannot (at least not in good faith) argue with an explicit statement from the rules.
Say you have advantage on a d20 test and fail with both rolls. If you have Heroic Inspiration, then you can expend it to reroll once and must use the new roll. What if you have a means to give yourself advantage on a roll (e.g., Tides of Chaos)? Can that be applied to give you advantage on the Heroic Inspiration reroll?
It's not possible to use Advantage (EDIT: or Disadvantage) in the Heroic Inspiration reroll:
That's the question: whether advantage can be applied to a heroic inspiration reroll. Both excerpts you provide highlight the "one reroll." But it's unclear to me whether advantage can be applied to that reroll (which I understand is still a roll for d20 test).
You are re-rolling one die, not making a brand new D20 test and thus you only get to re-roll that one die.
No, I wouldn’t allow that because, HI is used to replace 1 failed roll. It’s not a total do over. Also in my opinion it would make HI way over powered. Not something I would do or would allow. Also RAW “reroll 1 failed d20 test”, not reverse time and total do over.
Thanks for your answers!
It's worth pointing out that the "reroll one die" limitation also applies to things like damage rolls. For instance if you cast Shatter, which does 3d8 damage, and get a 1, a 1, and an 8, you can use Heroic Inspiration to reroll one of those 1s, but not both of them.
pronouns: he/she/they
What if you have advantage, say roll a 14 and 8. You decide to use HI to reroll the 8 and get a 1. Do you have to take the 1?
No, re-rolls from Heroic Inspiration are done before success/failure is determined. So first you had 14/8 to choose from but after the re-roll you instead have 14/1 to choose from but you still pick the highest and that would be the 14 in both cases.
Exactly. That's what the rule says (green text added by me):
Nope, since you must use the new roll, you must reroll both, since you can't use the lower roll if the new lower roll is lower due to Advantage, and you can't use the higher roll if the reroll is higher with the Disadvantage... Advantage says you use the Higher Roll, Disadvantage says you must use the lower roll, Heroic Inspiration says you use the new roll, for both to work, you MUST reroll both so you are guaranteed the new roll is the correct roll for Advantage or Disadvantage... Anyone who says Otherwise didn't read the wording of all three.
Please read again Heroic Inspiration let you reroll one of those dice, not both of them.
If it helps you understand the interaction, you can check out this related thread: Advantage on Initiative and Halfling Luck
"You must use the new roll" means the new roll is used in place of the roll you're re-rolling. It doesn't mean you must use it for the final outcome of the ability check, damage roll, etc.
For example, you're making a d20 test and roll an 11. You decide to use Heroic Inspiration and re-roll it, rolling a 6. You can't choose to keep the original 11, you must use the 6 as the result of that dice roll.
However, let's say you had advantage on that same d20 test and rolled a 7 and a 12. You decide to Heroic Inspiration that 12 (for whatever reason) and roll instead a 4. "You must use the new roll" doesn't mean "Even though you rolled a 4 and a 12, you must use the 4 ignoring the rules of advantage". It actually means "You cannot choose to keep the 12 instead of the re-rolled 4, you must take that 4." and then the rules for advantage apply and you use the 7.
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You must USE, not must pick from the new roll and the other half of the old roll... If you must use the new roll, you MUST use the new roll, not any part of the old roll... the other die would be the old roll... ergo, vis a vi, the only way to do it is to reroll both, because no one would ever reroll the higher roll on advantage nor disadvantage rolls, since rerolling the lower roll always would benefit more, while if you roll both you are taking a risk of losing the benefit of better rolls.
Your example is invalid, because you would automatically never choose the 12... you would always choose the 7, hoping to get a 13+, making the 12 the lower roll, while with advantage you would roll the 7, also hoping for something much higher that the 12 so you get the higher roll... rolling both means you could get a 2 and a 3, both lower that then 7 and have to take the lower on disadvantage and the higher on advantage, which is still a 2 and a 3... not a 7 nor a 12 either way...
Only way to make sure it is advantage/disadvantage is to reroll both
That would amount to Advantage or Disadvantage rolling a third die, which is not how Interactions with Rerolls like Heroic Inspiration works.
"You must use the new roll" very simply means you cannot choose to keep the old roll of that dice. It does not mean it must be used in the final determination of the overall d20 test.
My example is not invalid because there's no rule forcing you to choose the worse dice. Yes, I'll concede, choosing the better dice is not a sensible choice, but it's still a valid one. You're projecting "This is not something I would ever choose to do" into "This is not something anyone ever would choose to do" and then projecting that onto "This is not something the rules allow you to do". That is invalid.
Nope, as is explicitly stated in the Basic Rules/Player's Handbook
You cannot (at least not in good faith) argue with an explicit statement from the rules.
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