D&D 5E Using booming blade on a reaction attack with sanctuary question

[Irlo]

Triggers as a general rule must complete before the reaction can happen.

Can you cite the rule? I can't find it. The general rule seems to be "follow whatever timing is specified in the reaction's description."

We have this from the DMG:

Typical combatants rely on the opportunity attack and the Ready action for most of their reactions in a fight. Various spells and features give a creature more reaction options, and sometimes the timing of a reaction can be difficult to adjudicate. Use this rule of thumb: follow whatever timing is specified in the reaction’s description. For example, the opportunity attack and the shield spell are clear about the fact that they can interrupt their triggers. If a reaction has no timing specified, or the timing is unclear, the reaction occurs after its trigger finishes, as in the Ready action.

 

[Maxperson]

Can you cite the rule? I can't find it. The general rule seems to be "follow whatever timing is specified in the reaction's description."

We have this from the DMG:

That's for the timing on when the AOO happens. From that rule we can see that usually the trigger has to fully complete before the AOO happens. At no point in that section, the general reactions section in the PHB, or in the section about AOO when moving out of reach is there any language that says or implies that an interrupted action can change and/or remove the reaction trigger while still allowing the reaction. For that to happen you'd need specific language doing that. Otherwise the default would be to continue the action after the interruption.

 

[Irlo]

That's for the timing on when the AOO happens. From that rule we can see that usually the trigger has to fully complete before the AOO happens. At no point in that section, the general reactions section in the PHB, or in the section about AOO when moving out of reach is there any language that says or implies that an interrupted action can change and/or remove the reaction trigger while still allowing the reaction. For that to happen you'd need specific language doing that. Otherwise the default would be to continue the action after the interruption.

Okay, so there's no general rule to cite? That's okay. Your inference is a reasonable one, but I can't see that it's explicit in the rules. Reactions are best dealt with specifically, rather than with general rules, because there's so much variety.

I wouldn't allow an attacker to "take back" an attack that was interrupted by a shield spell, but I would probably allow movement that provoked an OA to be aborted (either by choice or by an effect brought on by the OA). But I see movement as a special case. I wouldn't object to a DM who ruled otherwise.

 

[ECMO3]

Okay, so there's no general rule to cite? That's okay. Your inference is a reasonable one, but I can't see that it's explicit in the rules. Reactions are best dealt with specifically, rather than with general rules, because there's so much variety.

I wouldn't allow an attacker to "take back" an attack that was interrupted by a shield spell, but I would probably allow movement that provoked an OA to be aborted (either by choice or by an effect brought on by the OA). But I see movement as a special case. I wouldn't object to a DM who ruled otherwise.

So if you walk 25 feet across a room towards someone with polarm master and he makes his AOO when you enter his reach you can abort the entire move and go back to where you started moving from 25 feet away?

Or how about if you start outside someone's reach, 15 feet away and then you walk past them and provoke an AOO (lets say they are invisible and you don't know they are there). You can now abort the entire move and go back to where you started moving from?

I have no problem with interrupting the movement and stopping it at the point he is attacked - he was going to move further, now he isn't. That is reasonable. My problem is with suggesting he did not move at all or that he is in the same place he started his turn in.

Whether he moved 1 foot or 100 feet before he triggered the AOO, he still moved and that caused an opportunity attack. The movement (no matter how much or how little) is what caused an opportunity attack and it happened. There is no way to suggest otherwise.

 

[Irlo]

So if you walk 25 feet across a room towards someone with polarm master and he makes his AOO when you enter his reach you can abort the entire move and go back to where you started moving from 25 feet away?

No, I don't think that's a reasonable ruling, for a few reasons but mostly because PAM doesn't specify that the AO happens just before the target enters reach. I was thinking specifically of a standard AO triggered by leaving reach with the attack resolving before the move is complete.

 

[ECMO3]

No, I don't think that's a reasonable ruling, for a few reasons but mostly because PAM doesn't specify that the AO happens just before the target enters reach. I was thinking specifically of a standard AO triggered by leaving reach with the attack resolving before the move is complete.

What makes 5 feet reasonable but 25 feet not reasonable?

What about my second example - you walk past an invisible creature and he makes his AOO when you leave his reach. Now you can abort the move and go all the way back to where you started.

How about I circle/spiral around someone 3 times gradually getting further and further away each rotation until I finally leave his reach the third time circling him. So I have walked about 45 feet of movement and moved about 2 feet further away from him in the last time I circled (15 feet) I walked and that 2 feet is what put me out of his reach. Do I go back to where I was before I circled him? Do I get 2 feet closer? Do I get 5 feet closer? How far do I go back?

I can totally buy the argument that you have not left his reach, you are at the very limit of it and still within his reach and can abort any further movement (and attack if you have the same reach as me). I can't buy that you have not moved at all, because whether you have to move 1 foot to leave my reach or 100 feet to leave my reach you still have to move.

I mean if we are going to say this what is the limit 1 inch, 1 foot, 5 feet, 15 feet, how much movement can I "take back" and why is it THAT number.

 

[Plaguescarred]

Polearm Master is more specific as it requires the creature to be within reach in order to work, or else it couldn't be attacked. This is also the Dev opinion;

 

[Plaguescarred]

I mean if we are going to say this what is the limit 1 inch, 1 foot, 5 feet, 15 feet, how much movement can I "take back" and why is it THAT number.

The last feet making you change space/square, because its the ammount making you move by increment so you can change space/square.

Moving a 4 feet or less means you are still within your 5 feet space/square. Moving 5 feet makes you change space/square

 

[Irlo]

What makes 5 feet reasonable but 25 feet not reasonable?

5' is the increment of movement that provokes an attack that occurs before that 5' movement is completed.

What about my second example - you walk past an invisible creature and he makes his AOO when you leave his reach. Now you can abort the move and go all the way back to where you started.

No, I would suggest that after the OA from the invisible creature, you can stop where you are -- adjacent to the creature, not all the way back to where you started. Again, it's because the attack occurs just before moving out of reach.

How about I circle/spiral around someone 3 times gradually getting further and further away each rotation until I finally leave his reach the third time circling him. So I have walked about 45 feet of movement and moved about 2 feet further away from him in the last time I circled (15 feet) I walked and that 2 feet is what put me out of his reach. Do I go back to where I was before I circled him? Do I get 2 feet closer? Do I get 5 feet closer? How far do I go back?

No, that's not what I'm suggesting at all. Only that last bit of movement that provokes the OA.

I can totally buy the argument that you have not left his reach, you are at the very limit of it and still within his reach and can abort any further movement (and attack if you have the same reach as me). I can't buy that you have not moved at all, because whether you have to move 1 foot to leave my reach or 100 feet to leave my reach you still have to move.

I wouldn't argue that you haven't moved at all.

I mean if we are going to say this what is the limit 1 inch, 1 foot, 5 feet, 15 feet, how much movement can I "take back" and why is it THAT number.

5' is the number. Why? Because any movement less than 5' is abstracted in the rules as remaining in the same space.

It's a reasonable DM ruling to say that you must finish moving out of reach after the OA resolves. It's also reasonable to say that you don't have to.

 

[ECMO3]

The last feet making you change space/square, because its the ammount making you move by increment so you can change space/square.

Using a grid is an optional rule to start with and not one that supports this argument in the rules anyway.

Moving a 4 feet or less means you are still within your 5 feet space/square. Moving 5 feet makes you change space/square

Moving 4 feet or less means you did not leave my reach and did not cause an AOO. You need to move 5 feet to get to the end of my reach. If you say 5 feet puts you in the next square then it puts you in the next square when the AOO happens.