Precise timing of attack rolls against players

[Chronos]

Players have multiple ways to use reactions to increase their armor class against an incoming attack. For instance, there's the Shield spell, which you can use in response to being hit to give you +5 AC, including against that hit (possibly turning it into a miss). It can fail: Maybe, unbeknownst to you, the monster rolled well enough that it still hits, even against your increased AC. To make it a meaningful decision, you have to not know how well the monster rolled when you choose to cast the Shield spell.

Alternately, you can have an inspiration die granted by a valor bard. In that case, you can use your reaction to roll an extra die and add that to your AC. This, you have to choose to use after you see the attacker's die roll, but before you know whether it hits or misses. And this too can fail: Maybe you use it when you didn't even need it, because the monster would have hit anyway, and maybe you use it and the monster still hits (for instance, if the inspiration die roll is low).

But what if both are possible? Maybe when combat started, the bard knew that the wizard was squishy, and so he gave her an inspiration die. And the wizard also knew that she was squishy, and so she prepared Shield as one of her spells. She can now use either ability against an attack. How does the DM give the player a fair opportunity to use these defensive abilities, while at the same time not giving away too much information?

[Waterdeep Merch]

Players have multiple ways to use reactions to increase their armor class against an incoming attack. For instance, there's the Shield spell, which you can use in response to being hit to give you +5 AC, including against that hit (possibly turning it into a miss). It can fail: Maybe, unbeknownst to you, the monster rolled well enough that it still hits, even against your increased AC. To make it a meaningful decision, you have to not know how well the monster rolled when you choose to cast the Shield spell.

Alternately, you can have an inspiration die granted by a valor bard. In that case, you can use your reaction to roll an extra die and add that to your AC. This, you have to choose to use after you see the attacker's die roll, but before you know whether it hits or misses. And this too can fail: Maybe you use it when you didn't even need it, because the monster would have hit anyway, and maybe you use it and the monster still hits (for instance, if the inspiration die roll is low).

But what if both are possible? Maybe when combat started, the bard knew that the wizard was squishy, and so he gave her an inspiration die. And the wizard also knew that she was squishy, and so she prepared Shield as one of her spells. She can now use either ability against an attack. How does the DM give the player a fair opportunity to use these defensive abilities, while at the same time not giving away too much information?

Since they're both expendable resources anyway, let them decide which one they want to try first. After they do so and call the change to their AC, tell them if that worked or not. If it didn't, give them an opportunity to use the other as well.

Though I'm assuming you'd tell them up front if the hit was a critical, right? It'd be just cruel to let them try to protect themselves when it's simply not possible.

[Chronos]

It's not a matter of which one to use first. You can't use both, because both use your reaction. And the opportunity for Inspiration has to come before the opportunity for Shield, because Inspiration is specifically before you find out if it hit, and Shield is after you find out.

Rather, there has to be some point at which you're deciding whether to use Inspiration, and you have to know some level of information at that time. And if you decide not to use it, then there comes a point when you decide whether to use Shield, and there's some level of information at that time. What should that information be, at each point, to be enough to be fair but not too much?

[Man_Over_Game]

It's not a matter of which one to use first. You can't use both, because both use your reaction. And the opportunity for Inspiration has to come before the opportunity for Shield, because Inspiration is specifically before you find out if it hit, and Shield is after you find out.


There is a different direction that's applicable, which is a Lore Bard using their Reaction on you, while you could cast Shield.

[stoutstien]

I roll behind a screen and I think you should tell a player when they're getting a critical hit.
In the case with shield and Bard inspiration I think shield would have to be used first due to wording but that's just the way I would rule not raw.
Shield- the reaction that can prevent the action that caused the reaction to take place.🤣

[MaxWilson]

But what if both are possible? Maybe when combat started, the bard knew that the wizard was squishy, and so he gave her an inspiration die. And the wizard also knew that she was squishy, and so she prepared Shield as one of her spells. She can now use either ability against an attack. How does the DM give the player a fair opportunity to use these defensive abilities, while at the same time not giving away too much information?

Since Bardic Inspiration/Cutting Words is supposed to happen before you know the results of the roll, it needs to go first. In this rare situation it could go something like this:

DM: The Fire Giant swipes at Grog with his greatsword. Lara, are you going to use Cutting Words?

Lara: Only if it's between 9 and 13.

DM: [rolls dice where Grog's player can't see them] Oho, it looks too close for comfort, and Lara whistles shrilly to distract the giant. Roll your die Lara.

Lara: [rolls] 6.

DM: The giant twitches involuntarily but it isn't enough to save Grog. Grog, you're hit! Will you Shield?

Grog: Yep.

DM: Seeing that you're about to be sliced in half by a ten-foot-long greatsword, you make a warding gesture to harden your body to withstand the blow. The giant's sword rings off your armor without doing any damage. Please expend two spell points.

If you really wanted to keep the information completely separate you could do the die-rolling with Lara in a way that Grog's player doesn't what numbers Lara declared (e.g. pass a note to the DM) or what the die result is (have the DM roll the d8).

This avoids "leaking" information to Grog that he shouldn't have, i.e. the exact die roll. That's especially important in the case of a crit, e.g. if Lara doesn't use her Cutting Words, should Grog Shield anyway or is it maybe useless?

Is it clunky? Yes, but that's 5E for you: lots of interrupts and exceptions to the rules all interacting with each other at once. Hopefully this won't come up very often, but when it does the above is how I'd handle it.

[Chronos]

OK, but what if it's a valor bard inspiration already assigned to Grog the wizard, which can be used for AC? Now it's the same player who has to decide whether to use the inspiration as has to decide whether to use the shield.

[Tanarii]

How does the DM give the player a fair opportunity to use these defensive abilities, while at the same time not giving away too much information?
If they can't read the die roll from where they are sitting, tell them what the result was.

Don't include bonuses. They only get to know the die, not the total result. Unless you want to give them that.

[Man_Over_Game]

If they can't read the die roll from where they are sitting, tell them what the result was.

Don't include bonuses. They only get to know the die, not the total result. Unless you want to give them that.

The catch is, they'll immediately know the attack values afterwards.

"The roll was 9"
"Alright, I don't use my Cutting Words feature"
"Ok. That's a 16 to hit".

[Tanarii]

The catch is, they'll immediately know the attack values afterwards.

"The roll was 9"
"Alright, I don't use my Cutting Words feature"
"Ok. That's a 16 to hit".Only if you announce totals. That's not required. But multiple PHB features work on the player knowing the die roll. Cutting Words is one.

Edit: yes, it's pretty common to announce results. No particular reason not too, nor to keep creature stats opaque. It's just that nothing is set up to require it to work. Whereas many are set up to use the die roll, before the final total is determined.

[Man_Over_Game]

Only if you announce totals. That's not required. But multiple PHB features work on the player knowing the die roll. Cutting Words is one.

That's a solid approach. Rather than announcing the total, just request the player's AC and announce whether you hit or not. I could see that working out.

[MaxWilson]

OK, but what if it's a valor bard inspiration already assigned to Grog the wizard, which can be used for AC? Now it's the same player who has to decide whether to use the inspiration as has to decide whether to use the shield.

It's no different than before. Grog just says "I'll use Inspiration if it's between 9 and 13." If he doesn't use it, the DM will tell him if he's been "hit" so he can decide whether or not to Shield instead.