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

[Maxperson]

Its exactly what i said ''the Opportunity Attack trigger is when it moves out but occur before it.''

What you said was that the trigger was '''has left reach''. It's not

Then I'm not sure what the issue is. The trigger is when it moves out of reach. That is the one and only trigger. That you attack before it leaves does not keep that trigger from happening. The trigger must occur in order for the AOO to happen. The enemy "moves out of reach."

 

[Stoutstien]

Then I'm not sure what the issue is. The trigger is when it moves out of reach. That is the one and only trigger. That you attack before it leaves does not keep that trigger from happening. The trigger must occur in order for the AOO to happen. The enemy "moves out of reach."

See the shield spell. An attack hitting is the trigger and the reaction states it applies to the triggering attack. If it turns a hit into a miss the trigger didn't happen. Sometimes the RaWs are stupid and form logic circles DMs have to deal with.

 

[Maxperson]

See the shield spell. An attack hitting is the trigger and the reaction states it applies to the triggering attack. If it turns a hit into a miss the trigger didn't happen. Sometimes the RaWs are stupid and form logic circles DMs have to deal with.

Examples of specific beats general don't help your position. Shield is a specific exception.

 

[Irlo]

[IMO] Moving out of reach is a process with a duration, not a quantum event. That is, there's time for the triggered OA to occur during that process. The rules are not logically rigorous or internally consistent. It's only as hard to resolve these things in-game as the DM wants to make it.

 

[Nikosandros]

I'm not precisely understand what you mean by interrupt. If you mean it in a general English word sense, I think I agree with you.

If they have moved out of range to trigger an OA (which happens right before they move out of range), they have done that. The OA still triggers. If, after that, since they technically have not yet moved out of range they wish to not continue moving so they stay in the same square, that's fine. They have moved "just shy" of 5 feet, so I would count that part of movement used in case they decide to move later int he round, or do something late requires movement like if they were proned in the OA.

A different example is a creature that declares it's moving across an area that's they don't know has been hit with Spike Growth - they can stop moving, reverse their movement, or do anything - they aren't bound by the declaration of their original destination, each square is it's own choice.

Yes, that's what I meant. We are in agreement.

 

[Stoutstien]

Examples of specific beats general don't help your position. Shield is a specific exception.

That's not how specific rules work. Specific rules can contradict general rules but those special rules still have to work with at least themselves. Shield says you must be hit to trigger the reaction bit the reaction can prevent the trigger. It doesn't include a clause to exempt that attack from fulfilling the requirements so you just have to go with the RAI/RTMS.

Any reaction that somehow retroactively occurs before the trigger is already in trouble and if they can potentially prevent the trigger they are asking for confusion.
When next was in playtest reactions were different and as they moved forward it got lost in the shuffle. The good news with AOs is the general reaction rules still apply which allows the target to continue their turn with the knowledge the reaction occured at that point in time. I.e. they can stop moving even if it retroactively prevents the trigger. It says "can"continue not "must".

 

[Maxperson]

That's not how specific rules work. Specific rules can contradict general rules but those special rules still have to work with at least themselves. Shield says you must be hit to trigger the reaction bit the reaction can prevent the trigger. It doesn't include a clause to exempt that attack from fulfilling the requirements so you just have to go with the RAI/RTMS.

It does.

"An invisible barrier of magical force appears and protects you. Until the start of your next turn, you have a +5 bonus to AC, including against the triggering attack, and you take no damage from magic missile."

It specifically includes the triggering attack as also having to overcome the increase in AC, which can turn the hit into a miss. There is no such language in the AOO from moving out of reach. Nothing there says or implies that the AOO can unwind the trigger the way the Shield spell does.

Any reaction that somehow retroactively occurs before the trigger is already in trouble and if they can potentially prevent the trigger they are asking for confusion.

There is no such potential to unwind the trigger in the movement AOO. It simply happens as the creature steps 5 feet away.

The good news with AOs is the general reaction rules still apply which allows the target to continue their turn with the knowledge the reaction occured at that point in time. I.e. they can stop moving even if it retroactively prevents the trigger. It says "can"continue not "must".

If it has the option not to continue, then the trigger never happened and therefore the AOO never happened. There is no specific language in either the general reaction rules or in the movement AOO that allows the AOO to prevent the trigger from happening, yet still occur.

 

[Irlo]

There is no specific language in either the general reaction rules or in the movement AOO that allows the AOO to prevent the trigger from happening, yet still occur.

Can you cite the general reaction rule that says an event that triggers an interrupting reaction must be completed following resolution of the reaction? I find precious few general rules about reactions. I may be overlooking something.

 

[Stoutstien]

It does.

"An invisible barrier of magical force appears and protects you. Until the start of your next turn, you have a +5 bonus to AC, including against the triggering attack, and you take no damage from magic missile."

It specifically includes the triggering attack as also having to overcome the increase in AC, which can turn the hit into a miss. There is no such language in the AOO from moving out of reach. Nothing there says or implies that the AOO can unwind the trigger the way the Shield spell does.


There is no such potential to unwind the trigger in the movement AOO. It simply happens as the creature steps 5 feet away.

If it has the option not to continue, then the trigger never happened and therefore the AOO never happened. There is no specific language in either the general reaction rules or in the movement AOO that allows the AOO to prevent the trigger from happening, yet still occur.

Your logic on why shield work is exactly why AOs can trigger even if the "out of range" criteria isn't met retroactively.

 

[Maxperson]

Can you cite the general reaction rule that says an event that triggers an interrupting reaction must be completed following resolution of the reaction? I find precious few general rules about reactions. I may be overlooking something.

Triggers as a general rule must complete before the reaction can happen. A very few allow you to interrupt the trigger. No rule says that the interruption stops the trigger, so it defaults to completion. To stop the trigger, while still getting the reaction triggered by that trigger, you would need specific language saying so. Shield specifies that it the AC can affect the "hit" that triggered it. Sentinel specifies that it drops the speed to 0 when it is triggered.