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

[cbwjm]

I think they'd still use up at least 5 feet of movement

 

[Nikosandros]

I think they'd still use up at least 5 feet of movement

I agree on that.

 

[Lycurgon]

1 - enemy starts to move away
2 - AoO triggers and is taken before the enemy leaves their square. Sanctuary drops.
3 - Enemy can decide not to move:
3a - if they move they take damage from Booming Blade for moving, they only take this once because the 2 uses of it overlap and trigger at the same time.
3b - if they decide not to move they do not take the extra damage from Booming blade and is standing next to the PC. They can attack them if they like.

When Booming Blade is used on someone they can decide to stop moving to avoid the extra damage from moving.

 

[FarBeyondC]

Booming blade doesn’t target an enemy. It has a range of “self” and the effect of allowing you to make a melee weapon attack with the weapon used for the material component, which has a special effect if it hits.

Like I said, it’s ambiguous enough that I can see how someone might interpret it differently, and it’s not really relevant to the topic. But that’s my understanding of how Booming Blade works.

The Range of Self in this instance clearly refers to the point of origin of the spell, and not its target.

 

[Plaguescarred]

The enemy doesn't have to move after being hit by an Opportunity Attack according to the Devs
So the sequence would go more as follow. Enemy is sheathed in booming energy to start his turn and right next to me.

Enemies Turn:
1. Enemy attempt moving out of my reach, triggering an AOO
2. Cast Booming Blade via War Caster, hitting it and sheathing it in booming energy
3. Sanctuary drops
4. The enemy either keep moving and take damage from Booming Blade or stay within 5 feet of me and attack me

 

[Krachek]

For war caster, yes it works with booming blade.
Sage advice

 

[Charlaquin]

The Range of Self in this instance clearly refers to the point of origin of the spell, and not its target.

Right, but the text of the spell doesn’t talk about targeting a creature with the spell, only with a melee weapon attack.

 

[Charlaquin]

For war caster, yes it works with booming blade.
Sage advice

And as I said, I think it’s ambiguous enough I can see how this reading works, and it also isn’t relevant to the topic.

 

[Charlaquin]

Somewhat related to the question at hand: do you people allow someone who has been targeted by an OA triggered by leaving reach to interrupt their movement and decide to remain where they are?

I’ve never seen a case where someone wanted to do that, but sure.

 

[Blue]

Somewhat related to the question at hand: do you people allow someone who has been targeted by an OA triggered by leaving reach to interrupt their movement and decide to remain where they are?

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.