You can cast Booming Blade if a creature triggers an opportunity attack from you and you have the War Caster feat. Booming Blade states: "You brandish the weapon used in the spell's casting and make a melee attack with it against one creature within 5 feet of you." So, basically, "when a hostile creature's movement provokes an opportunity attack from you, you can use your reaction to cast a spell at the creature" (text from the War Caster feat), and Booming Blade needs that hostile creature to be targeted.
EDIT (I hadn't interpreted the spell correctly at the moment of writing this -- Booming Blade doesn't create an AoE) The range stated in Booming Blade, Self (5-foot radius), is about the Area of Effect that is set after you hit the creature, so after that, if the target "moves 5 feet or more before then, the target takes 1d8 thunder damage" (text from Booming Blade spell)
Tricky thing, but Booming Blade cannot be used against unwilling creatures. I agree with the first answer provided by @Plaguescarred
EDIT: "Self (5-foot radius)" isn't the same as "Self".
The range stated in Booming Blade, Self (5-foot radius), is about the Area of Effect that is set after you hit the creature, so after that, if the target "moves 5 feet or more before then, the target takes 1d8 thunder damage" (text from Booming Blade spell)
This is incorrect and is exactly backwards. The AOE is set before anything having to do with the creature. In fact, if the creature was not yet in the area of effect when it was struck by the weapon then the rest of the description for what happens to that creature would not apply. These things only happen to the creature because it is standing within an area of effect when it is struck by the qualifying attack. Booming Blade is an AOE spell. Not a spell attack spell.
Let me try a more detailed description of how it might be helpful to envision this. Picture the spellcaster casting the spell on his weapon. The weapon then instantly radiates an invisible magical sphere which does not move with the weapon (and therefore, technically it wasn't cast on the weapon, but at the weapon's location). Just for fun, maybe the weapon flashes brightly for an instant when the spell is cast upon it. Now, right away, the spellcaster immediately selects a creature within the AOE that will be affected by that AOE if such an affect can be successfully triggered. The spellcaster attacks the creature with THAT weapon. On a hit, the creature interacts with the AOE and suffers the effect of it in addition to suffering the damage from the weapon attack.
Keep in mind, this spell was affected by errata along the way. Originally the spell actually had a range of 5 feet and the creature being attacked was "within range". The spell actually works differently under those parameters. The spell was explicitly and deliberately changed to have a range of self and the creature had to be within the area of effect, not within the range of the spell. This is now an AOE spell.
The range of booming blade ' is''Range: Self (5-foot radius)''
Creatures affected by a spell are the target of it.
Target: A typical spell requires you to pick one or more targets to be affected by the spell's magic. A spell's description tells you whether the spell targets creatures, objects, or a point of origin for an area of effect (described below).
Saving Throws: Many spells specify that a target can make a saving throw to avoid some or all of a spell's effects. The spell specifies the ability that the target uses for the save and what happens on a success or failure.
Ok, we really shouldn't spend too many posts in this thread debating what the term "targeting" means in the game since we've already done that in other threads. In my opinion, your interpretation is wrong. Spells which create an AOE that affect one or more creatures are NOT targeting those creatures. That's just not what targeting means. Just because you can find a couple of specific rules and a few specific spell descriptions that use the word erroneously, as I've already mentioned, that does not mean that we should just ignore how the term is defined in the general rules for spellcasting within the Range and Targets sections of Chapter 10. That's where the game design for how spellcasting actually works is written.
EDIT: avoid making references to the spell's 5 ft. range to prevent confusions. I apologize for using them to draw correlations; that was a mistake.
EDIT2: I hadn't interpreted the spell correctly at the moment of writing this.
In this case, "Self (5-foot radius)" specifies the range of the attack as well as is the Area of Effect, but technically this Area of Effect is not created at the instant of casting Booming Blade. is the reach of the melee attack.
Everything is explained in the description of Booming Blade:
First, you need to make a melee attack. It is not a spell attack but it is a melee attack with the weapon against one creature within 5 feet of you (the spell's range, indeed), instead of affecting an imaginary Area of Effect around you: initially, it affects only your weapon and, maybe, the creature you targeted.
If the attack misses the target, there is no Area of Effect to consider. From the spell: "On a hit, the target suffers the weapon attack's normal effects and then becomes sheathed in booming energy until the start of your next turn". If you miss, you cannot create any Area of Effect.
If the target willingly moves 5 feet (again, the range of the spell) or more before then, the target takes 1d8 thunder damage, and the spell ends.
We have clarification on this in the Sage Advice Compendium regarding the intent of Booming Blade and opportunity attacks: "it can’t be used to make an opportunity attack, unless a special feature allows you to do so", like the War Caster feat.
Can you use green-flame blade and booming blade with Extra Attack, opportunity attacks, Sneak Attack, and other weapon attack options?
Introduced in the Sword Coast Adventurer’s Guide , the green-flame blade and booming blade spells pose a number of questions, because they each do something unusual: require you to make a melee attack with a weapon as part of the spell’s casting.
First, each of these spells involves a normal melee weapon attack, not a spell attack, so you use whatever ability modifier you normally use with the weapon. (A spell tells you if it includes a spell attack, and neither of these spells do.) For example, if you use a longsword with green-flame blade, you use your Strength modifier for the weapon’s attack and damage rolls.
Second, neither green-flame blade nor booming blade works with Extra Attack or any other feature that requires the Attack action. Like other spells, these cantrips require the Cast a Spell action, not the Attack action, and they can’t be used to make an opportunity attack, unless a special feature allows you to do so.
Third, these weapon attacks work with Sneak Attack if they fulfill the normal requirements for that feature. For example, if you have the Sneak Attack feature and cast green-flame blade with a finesse weapon, you can deal Sneak Attack damage to the target of the weapon attack if you have advantage on the attack roll and hit.
Tricky thing, but Booming Blade cannot be used against unwilling creatures. I agree with the first answer provided by @Plaguescarred
Fair enough. But it's not a big deal because they'll trigger booming blade from their movement on their next turn. Either they choose not to move and essentially pass or they'll move and take the damage. It's still better than just using your weapon.
So to recap it seems these are the elements of the combo up for discussion.
1. Does dissonant whispers provoke an opportunity attack? This hasn't been challenged, but I would say this is definitively answered by the rules. The only exceptions for provoking opportunity by moving out of range are for the disengage action, teleporting, and being moved by someone or something without using a movement, action, or reaction to do so. Dissonant whispers requires the use of a reaction, so it is not exempt from provoking.
2. Can booming blade be used with warcaster for an opportunity attack? This is the debated topic, but it seems like the answer is yes because booming blade requires you to make a melee attack on a creature within range, which satisfies the condition that the spell must be cast "at" a creature.
3. Does the movement from dissonant whispers trigger the thunder damage? The problem here is the interpretation of willing movement. I interpreted this as identical to the criteria for opportunity attacks, but I can see the other side. It may be a DM discretion issue then, but it's not terribly impactful either way on the combo since they would still trigger the damage when they move toward you on their turn.
Anything not discussed or overlooked can still be valuable to this discourse, and I thank you all for your input.
Tarodnet, please stop posting incorrect information about this spell. You've been corrected multiple times now.
The Sage Advice on this topic that you keep referring to had the same wording at least as far back as September 2017 according to the Wayback Machine. As I already mentioned a couple of times in this thread, the Booming Blade spell had official errata which drastically changed the spell in the SCAG errata of 2020. So, any developer comments which may have been published before that time are completely obsolete.
The notation for the Range and Area parameters of every spell has a specific meaning. Whenever you see the exact notation of "Range: AAA (BBB)" the "AAA" always refers to the range of the spell and the "BBB" always indicates that the spell is an AOE spell with the AOE's size and shape specified there. Please do not confuse other readers by suggesting that maybe sometimes this notation actually could mean something else. It cannot. There are hundreds upon hundreds of officially published spells in the game and in every single case where you see the above notation it means exactly as I've described above. Every time. Even the developer comment posted earlier by plaguescarred gets it right:
@JeremyECrawford A note about D&D spells with a range of "Self (XYZ)": the parenthetical—which says "5-foot radius," "15-foot cone," or something else—means you are the spell's point of origin, but you aren't necessarily its target. You're creating an effect that originates in your space.
In this case, "Self (5-foot radius)" specifies the range of the attack as well as the Area of Effect
NOOOOOO!!!!! It absolutely does NOT mean this! This notation NEVER means this! See above. The range is "self". The size and shape of the AOE is "5-foot radius" (sphere implied).
technically this Area of Effect is not created at the instant of casting Booming Blade.
WRONG! It appears right there in the spell parameters! AND it appears in the first sentence of the spell description! The spell is quite literally creating an AOE with a specific effect that is triggered in a specific way. As soon as the spell is cast it creates an AOE for the duration.
NO. There is nothing first about it. You are making up words that are not there. The reason why the spell says that you suffer the weapon's normal effects and then you suffer the effects of the AOE is because that is literally how all AOE spells work when their effects need to be triggered. The triggering event occurs, and then the AOE (WHICH IS ALREADY THERE) affects the appropriate creature. For example, there are dozens of spells that say something like "when a creature enters the area or begins its turn there, [then] something happens". You don't say, the AOE causes damage to the creature and then the creature moves into the area. That would make no sense. The AOE is already there, a trigger occurs (such as entering the area) and then something happens to the creature.
a melee attack with the weapon against one creature within 5 feet of you (the spell's range, indeed)
Ok, you really need to stop saying this. Any reference to 5 feet is NOT the range of this spell. That is incorrect information, and you are confusing readers with this. The range of this spell is "self".
If the attack misses the target, there is no Area of Effect to consider . . . If you miss, you cannot create any Area of Effect.
This is incorrect, but at least it's a more reasonable mistake. The AOE is already there. It's created by the spell and specified by the spell parameters. If you miss, you just cannot trigger anything that actually affects a creature that is located within the AOE. But the AOE is there, it just doesn't do anything to the creature.
If the target willingly moves 5 feet (again, the range of the spell) or more before then, the target takes 1d8 thunder damage, and the spell ends.
This short piece of fiction is actually completely wrong twice, impressively enough.
First, this reference to 5 feet is NOT the range of the spell! This has nothing to do with the range of the spell! And we know that this cannot be the range of the spell because the range of the spell is "self"! You cannot be 5 feet away from yourself!
Second, this reference to 5 feet doesn't even have anything to do with that OTHER reference to 5 feet! They are totally unrelated! They happen to be using the same number by sheer coincidence. This reference to 5 feet is only talking about what happens to the affected creature if it moves this far before the start of your next turn. The creature does NOT even need to be moving outside of the AOE for this to trigger. It could be just circling around you but remaining close to you and it would still trigger this effect. It's literally just referring to distance travelled, not related at all to potentially crossing any sort of geographic boundary or anything of that sort. And definitely NOT related even one iota to the range of the spell.
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Look, I've already gone into plenty of detail and have provided all of the information for how this spell works. Use the information however you wish.
This is incorrect, but at least it's a more reasonable mistake. The AOE is already there. It's created by the spell and specified by the spell parameters. If you miss, you just cannot trigger anything that actually affects a creature that is located within the AOE. But the AOE is there, it just doesn't do anything to the creature.
So this is a part of your argument I don't understand. You say the AOE is triggered prior to the melee attack, but what's the effect? It can't be brandishing the weapon, because it says that's part of the casting... but there's no effect on the spell description prior to making the melee attack. So what's the effect in the AOE?
Ok, we really shouldn't spend too many posts in this thread debating what the term "targeting" means in the game since we've already done that in other threads. In my opinion, your interpretation is wrong. Spells which create an AOE that affect one or more creatures are NOT targeting those creatures. That's just not what targeting means. Just because you can find a couple of specific rules and a few specific spell descriptions that use the word erroneously, as I've already mentioned, that does not mean that we should just ignore how the term is defined in the general rules for spellcasting within the Range and Targets sections of Chapter 10. That's where the game design for how spellcasting actually works is written.
The entire argument here breaks down to a disagreement on what is meant by the word target (or more specifically Self(X radius) .. and what is considered the target of the booming blade cantrip) within D&D 5e and it is clear (due to several examples of different usages) that this is not well defined (target is semantically used in the rules for both the point in space that is the source of an AoE and the creatures affected by an AoE).
Stating that someone's interpretation is incorrect because you arbitrarily decide that some of the examples contained in RAW are "erroneous" in your opinion and then state someone else is wrong because they don't go along with your arbitrary revisions of RAW to match your preferred interpretation is just a logical fallacy. Both interpretations are possible for what the word "target" means within 5e.
This is why the game has and needs a DM to decide how these mechanics will be run in their game. It is also why there are several arguments out there (what a target IS, is just one of them) that have been discussed many times over the years with two or more positions on how the rules should be interpreted. Until those rules are officially updated or errata'ed, there is no way to state which of these positions is the "correct" one in terms of RAW since the terms involved (like "target") are not sufficiently well defined or may be used in multiple valid contexts within the rules.
The notation for the Range and Area parameters of every spell has a specific meaning. Whenever you see the exact notation of "Range: AAA (BBB)" the "AAA" always refers to the range of the spell and the "BBB" always indicates that the spell is an AOE spell with the AOE's size and shape specified there. Please do not confuse other readers by suggesting that maybe sometimes this notation actually could mean something else. [...]
EDIT (I hadn't interpreted the spell correctly at the moment of writing this. In my opinion, Booming Blade doesn't create an AoE)
That's absolutely true, but Booming Blade has a different description in its spell entry when you compare with an AoE spells. In my opinion, the AoE is not created if you don't hit the target Booming Blade doesn't create an AoE. You have a different opinion, and that's okay. Cone of Cold or Burning Hands describes the area of effect. Fireball describes the area. Or Ice Knife. Booming Blade doesn't, or not clearly to me.
In fact, what's the affected area really? The creature or your surroundings? It seems to be only the creature: "and then becomes sheathed in booming energy". My understanding, again.
The description of the spell:
You brandish the weapon used in the spell's casting and make a melee attack with it against one creature within 5 feet of you. On a hit, the target suffers the weapon attack's normal effects and then becomes sheathed in booming energy until the start of your next turn. If the target willingly moves 5 feet or more before then, the target takes 1d8 thunder damage, and the spell ends.
NO. There is nothing first about it. You are making up words that are not there. The reason why the spell says that you suffer the weapon's normal effects and then you suffer the effects of the AOE is because that is literally how all AOE spells work when their effects need to be triggered.
The first sentence is: "You brandish the weapon used in the spell's casting and make a melee attack" So the first thing to do is a melee attack.
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@up2ng, I agree with you about what Self (X' radius, line, etc.) means. The original post is about using Booming Blade when a creature triggers the opportunity attack, anyway.
I will edit my previous answer to remove some parts, as I used the 5 ft. value to explain myself, but it had the opposite effect. Sorry for the confusion.
So after looking into this, I find many aspects of this line of argument are immaterial. The main point of contention here is whether booming blade works with war caster. The requirement for this is that the spell is cast at the creature provoking, casting time is one action, and the spell must target only that creature.
The main argument is that booming blade targets self, not the creature. This is based on the range which is Self (5-foot radius). I find this is not correct. If exclude booming blade and green flame blade (since they're both similar and the spells we're debating), there are no spells with this range that target self. One example, thunderclap is an AOE that is centered around the caster but notably does not target the caster. It targets the area around the caster excluding the caster from the AOE. So based on the range, the spell does not target the caster in any case where this range is used.
So then we ask about AOE. There has been debate on whether AOE spells target the affected creatures, but I don't think it matters because it doesn't seem booming blade actually has an AOE. Looking at the details of the spell, what does it say? Firstly, it says You brandish the weapon used in the spell’s casting and make a melee attack with it against one creature within 5 feet of you. This clearly seems to be the requisite actions for casing the spell as is the norm for many spell descriptions. This means none of this is part of the spell's effect, which makes sense since none of it is magical. Next we have On a hit, the target suffers the weapon attack’s normal effects and then becomes sheathed in booming energy until the start of your next turn. If the target willingly moves 5 feet or more before then, the target takes 1d8 thunder damage, and the spell ends. So now we have effects of the spell, but who is affected? The target of the attack is the only creature affected.
Given only one creature is affected by the spell, it seems quite clear that the spell is single targeted at the creature being attacked. The range describes self being the center point of the spell and 5ft being the potential range of the spell's effect, which is to sheath a creature with booming energy. Given this interpretation, it seems clear that the booming blade does work with war caster. If we assume the target of the spell is self, then we have the absurdity that the target of the spell is not at all affected by the spell effect upon success. What other example of a spell is there where the spell target isn't affected by the effect of a spell?
So after looking into this, I find many aspects of this line of argument are immaterial. The main point of contention here is whether booming blade works with war caster. The requirement for this is that the spell is cast at the creature provoking, casting time is one action, and the spell must target only that creature.
The main argument is that booming blade targets self, not the creature. This is based on the range which is Self (5-foot radius). I find this is not correct. If exclude booming blade and green flame blade (since they're both similar and the spells we're debating), there are no spells with this range that target self. One example, thunderclap is an AOE that is centered around the caster but notably does not target the caster. It targets the area around the caster excluding the caster from the AOE. So based on the range, the spell does not target the caster in any case where this range is used.
So then we ask about AOE. There has been debate on whether AOE spells target the affected creatures, but I don't think it matters because it doesn't seem booming blade actually has an AOE. Looking at the details of the spell, what does it say? Firstly, it says You brandish the weapon used in the spell’s casting and make a melee attack with it against one creature within 5 feet of you. This clearly seems to be the requisite actions for casing the spell as is the norm for many spell descriptions. This means none of this is part of the spell's effect, which makes sense since none of it is magical. Next we have On a hit, the target suffers the weapon attack’s normal effects and then becomes sheathed in booming energy until the start of your next turn. If the target willingly moves 5 feet or more before then, the target takes 1d8 thunder damage, and the spell ends. So now we have effects of the spell, but who is affected? The target of the attack is the only creature affected.
Given only one creature is affected by the spell, it seems quite clear that the spell is single targeted at the creature being attacked. The range describes self being the center point of the spell and 5ft being the potential range of the spell's effect, which is to sheath a creature with booming energy. Given this interpretation, it seems clear that the booming blade does work with war caster. If we assume the target of the spell is self, then we have the absurdity that the target of the spell is not at all affected by the spell effect upon success. What other example of a spell is there where the spell target isn't affected by the effect of a spell?
The main problem with this approach is spells like Spirit Guardians that use the same wording for range as Booming Blade. Spirit Guardians is a spell with range Self (15' radius) which does not use the word "target" to describe the creatures affected by the spell. In the case of casting Spirit Guardians, I don't think there are many that would argue that the spellcaster is not the target of the spell (who is not affected unless the caster decides they want to be).
The problem is that Booming Blade uses the same terminology in describing the range of the spell as Self (5' radius) potentially implying that the spellcaster is the target. On the other hand, Booming Blade also explicitly calls the creature affected by the "energy" as the target of the spell "On a hit, the target suffers the weapon attack’s normal effects and then becomes sheathed in booming energy until the start of your next turn."
The specific clause of War Caster states:
"When a hostile creature's movement provokes an opportunity attack from you, you can use your reaction to cast a spell at the creature, rather than making an opportunity attack. The spell must have a casting time of 1 action and must target only that creature."
So, as mentioned earlier in the thread ... the entire argument devolves to what is the target of the spell. Target is used to both define the point the spell is aimed at AND creatures affected by the spell depending on what part of the rule book you read. In the case of Booming Blade, I rule that the target of the spell is the creature being attacked by the melee weapon used in the spell. This makes Booming Blade usable with War Caster when I am running the game but I am not going to say other interpretations (that rely on different interpretations of what a target for the spell is) are wrong.
The main problem with this approach is spells like Spirit Guardians that use the same wording for range as Booming Blade. Spirit Guardians is a spell with range Self (15' radius) which does not use the word "target" to describe the creatures affected by the spell. In the case of casting Spirit Guardians, I don't think there are many that would argue that the spellcaster is not the target of the spell (who is not affected unless the caster decides they want to be).
The problem is that Booming Blade uses the same terminology in describing the range of the spell as Self (5' radius) potentially implying that the spellcaster is the target. On the other hand, Booming Blade also explicitly calls the creature affected by the "energy" as the target of the spell "On a hit, the target suffers the weapon attack’s normal effects and then becomes sheathed in booming energy until the start of your next turn."
The specific clause of War Caster states:
"When a hostile creature's movement provokes an opportunity attack from you, you can use your reaction to cast a spell at the creature, rather than making an opportunity attack. The spell must have a casting time of 1 action and must target only that creature."
So, as mentioned earlier in the thread ... the entire argument devolves to what is the target of the spell. Target is used to both define the point the spell is aimed at AND creatures affected by the spell depending on what part of the rule book you read. In the case of Booming Blade, I rule that the target of the spell is the creature being attacked by the melee weapon used in the spell. This makes Booming Blade usable with War Caster when I am running the game but I am not going to say other interpretations (that rely on different interpretations of what a target for the spell is) are wrong.
I suppose Spirit Guardians does seem to pose a little quandary. Many would suppose that the caster is affected when it says "They flit around you to a distance of 15 feet for the duration." Arguably you could say that the caster is not a target, but the area around him is.
But even so it seems to me that booming blade still doesn't target the caster because there is no effect of the spell which affects the caster. And while Spirit Guardians explicitly affects an area, booming blade does not. Booming Blade merely affects the target of the attack, which is why I think the attack target is the sole target of the spell. Any other target would have to at least be affected by the spell, but there is no one other than the attacked creature. On this point we seem to be in agreement. While you may argue that affected creatures are necessarily spell targets, I argue that at least any target of the spell must be affected upon success. The caster is not affected, so he's not a target.
The main problem with this approach is spells like Spirit Guardians that use the same wording for range as Booming Blade. Spirit Guardians is a spell with range Self (15' radius) which does not use the word "target" to describe the creatures affected by the spell. In the case of casting Spirit Guardians, I don't think there are many that would argue that the spellcaster is not the target of the spell (who is not affected unless the caster decides they want to be).
The problem is that Booming Blade uses the same terminology in describing the range of the spell as Self (5' radius) potentially implying that the spellcaster is the target. On the other hand, Booming Blade also explicitly calls the creature affected by the "energy" as the target of the spell "On a hit, the target suffers the weapon attack’s normal effects and then becomes sheathed in booming energy until the start of your next turn."
The specific clause of War Caster states:
"When a hostile creature's movement provokes an opportunity attack from you, you can use your reaction to cast a spell at the creature, rather than making an opportunity attack. The spell must have a casting time of 1 action and must target only that creature."
So, as mentioned earlier in the thread ... the entire argument devolves to what is the target of the spell. Target is used to both define the point the spell is aimed at AND creatures affected by the spell depending on what part of the rule book you read. In the case of Booming Blade, I rule that the target of the spell is the creature being attacked by the melee weapon used in the spell. This makes Booming Blade usable with War Caster when I am running the game but I am not going to say other interpretations (that rely on different interpretations of what a target for the spell is) are wrong.
I suppose Spirit Guardians does seem to pose a little quandary. Many would suppose that the caster is affected when it says "They flit around you to a distance of 15 feet for the duration." Arguably you could say that the caster is not a target, but the area around him is.
But even so it seems to me that booming blade still doesn't target the caster because there is no effect of the spell which affects the caster. And while Spirit Guardians explicitly affects an area, booming blade does not. Booming Blade merely affects the target of the attack, which is why I think the attack target is the sole target of the spell. Any other target would have to at least be affected by the spell, but there is no one other than the attacked creature. On this point we seem to be in agreement. While you may argue that affected creatures are necessarily spell targets, I argue that at least any target of the spell must be affected upon success. The caster is not affected, so he's not a target.
You're correct that it doesn't target the caster. "Self" and "Self (Xft radius/cone)" are different, that's why they're written differently. "Self" targets the caster, "Self (Xft radius/cone/etc.)" targets an area or creatures in an area defined by the phrase in parenthesis and an origin of the caster. In the case of Booming Blade the caster is defined as the origin and "(5 ft radius)" defines an area around the origin from which you choose a creature to target with a melee attack. In other words: booming blade targets a single creature within 5 feet of the caster. Greenflame Blade may or may not target "only that creature" within 5 feet of the caster, depending on what you choose for the secondary target. (Note: a "spell that targets only that creature" is not necessarily a "spell with a single target", so when you choose the initial creature to receive the secondary damage of GFB, it does NOT have a single target but it does target only that creature.)
Eight multicolored rays of light flash from your hand. Each ray is a different color and has a different power and purpose. Each creature in a 60-foot cone must make a Dexterity saving throw. For each target, roll a d8 to determine which color ray affects it.
Like with booming blade, the targets are one or more creatures within the defined area, written in the spells range as "Self (60 ft )", that is, one or more creatures within a 60ft cone originating from the caster. This agrees with the previous post: the caster is not considered a target when the word "Self" in the range is followed by parenthesis; the target is instead the defined area or something(s) within it.
Thank you for the input. Debate here has focused on whether booming blade works with War Caster. But if we take for granted that it does, there seem to be no other objections to the combo. You can use dissonant whispers in melee range to cause opportunity attack and use booming blade for that attack (with War Caster assuming it works) to do the spell damage and weapon damage. There's question on whether it triggers the thunder damage right away, but even if it doesn't it's active on their next turn. Seems to me like a really good combo for a first level spell and cantrip.
Booming Blade and Green-Flame Blade are strange beasts, to be honest. That was one of the things I had in mind when I wrote my opinion about how Booming Blade works, but I think I failed miserably.
Thanks for the latest post about the difference between the two kinds of Self ranges.
So I wanted to bring up a consideration I thought of with the Thunder damage aspect here. This damage requires willing movement of at least 5 feet to trigger. This was briefly addressed by some to say the movement caused by the spell doesn't qualify as willing movement presumably because the creature doesn't choose to move.
One thing I wanted to bring up was the extra dimension of meta vs in game choices. It seems to me that the spell here only takes the creature's choice to move away from a meta game perspective. Dissonant whispers isn't a mind control spell. It essentially produces a sound that only the target hears which is so painful they instinctively react by moving away from it. This would be akin to getting stung by bees and instinctively running away from it. The point is it doesn't necessarily mean they didn't "willingly" move away in game. They just had such a compelling reason to move they couldn't consider it.
Now personally I think the spell should have the same criteria for willing movement as what is listed for opportunity attacks. With this, the fact that their reaction was used to move would be sufficient to trigger the damage. To suggest that a choice is needed suggests the booming energy is considering the psychological state of the subject for its trigger, which seems absurd. But what seems even more absurd is that the booming energy is actual considering the presence of a metagame choice available to the player or DM as a condition for the trigger.
So I thought this might be an important point of consideration. Does the spell compell movement for the character or the player? Does the spell consider the psychology of the character? Does it even further consider the metagame choices available? These are important implications for the role playing game. Potentially the metagame considerations would break emersion, which is an important aspect of the game.
Carric Aquissar, elven wannabe artist in his deconstructionist period (Archfey warlock) Lan Kidogo, mapach archaeologist and treasure hunter (Knowledge cleric) Mardan Ferres, elven private investigator obsessed with that one unsolved murder (Assassin rogue) Xhekhetiel, halfling survivor of a Betrayer Gods cult (Runechild sorcerer/fighter)
The meta perspective for "willingly" is did the player controlling the creature decide to do it or did the game make them do it. It has nothing to do with the creature's mental state and all to do with whether it was a player decision or not.
That's the problem I pointed out. Does it make sense that the spell has meta world detection for consideration of the trigger for damage?
I see many things here:
The range stated in Booming Blade, Self (5-foot radius), is about the Area of Effect that is set after you hit the creature, so after that, if the target "moves 5 feet or more before then, the target takes 1d8 thunder damage" (text from Booming Blade spell)EDIT: "Self (5-foot radius)" isn't the same as "Self".
This is incorrect and is exactly backwards. The AOE is set before anything having to do with the creature. In fact, if the creature was not yet in the area of effect when it was struck by the weapon then the rest of the description for what happens to that creature would not apply. These things only happen to the creature because it is standing within an area of effect when it is struck by the qualifying attack. Booming Blade is an AOE spell. Not a spell attack spell.
Let me try a more detailed description of how it might be helpful to envision this. Picture the spellcaster casting the spell on his weapon. The weapon then instantly radiates an invisible magical sphere which does not move with the weapon (and therefore, technically it wasn't cast on the weapon, but at the weapon's location). Just for fun, maybe the weapon flashes brightly for an instant when the spell is cast upon it. Now, right away, the spellcaster immediately selects a creature within the AOE that will be affected by that AOE if such an affect can be successfully triggered. The spellcaster attacks the creature with THAT weapon. On a hit, the creature interacts with the AOE and suffers the effect of it in addition to suffering the damage from the weapon attack.
Keep in mind, this spell was affected by errata along the way. Originally the spell actually had a range of 5 feet and the creature being attacked was "within range". The spell actually works differently under those parameters. The spell was explicitly and deliberately changed to have a range of self and the creature had to be within the area of effect, not within the range of the spell. This is now an AOE spell.
Ok, we really shouldn't spend too many posts in this thread debating what the term "targeting" means in the game since we've already done that in other threads. In my opinion, your interpretation is wrong. Spells which create an AOE that affect one or more creatures are NOT targeting those creatures. That's just not what targeting means. Just because you can find a couple of specific rules and a few specific spell descriptions that use the word erroneously, as I've already mentioned, that does not mean that we should just ignore how the term is defined in the general rules for spellcasting within the Range and Targets sections of Chapter 10. That's where the game design for how spellcasting actually works is written.
EDIT: avoid making references to the spell's 5 ft. range to prevent confusions. I apologize for using them to draw correlations; that was a mistake.
EDIT2: I hadn't interpreted the spell correctly at the moment of writing this.
In this case, "Self (5-foot radius)"
specifies the range of the attack as well as is the Area of Effect, but technically this Area of Effect is not created at the instant of casting Booming Blade.is the reach of the melee attack.Everything is explained in the description of Booming Blade:
(the spell's range, indeed), instead of affecting an imaginary Area of Effect around you: initially, it affects only your weapon and, maybe, the creature you targeted.If the attack misses the target, there is no Area of Effect to consider. From the spell: "On a hit, the target suffers the weapon attack's normal effects and then becomes sheathed in booming energy until the start of your next turn". If you miss, you cannot create any Area of Effect.(again, the range of the spell)or more before then, the target takes 1d8 thunder damage, and the spell ends.We have clarification on this in the Sage Advice Compendium regarding the intent of Booming Blade and opportunity attacks: "it can’t be used to make an opportunity attack, unless a special feature allows you to do so", like the War Caster feat.
Fair enough. But it's not a big deal because they'll trigger booming blade from their movement on their next turn. Either they choose not to move and essentially pass or they'll move and take the damage. It's still better than just using your weapon.
So to recap it seems these are the elements of the combo up for discussion.
1. Does dissonant whispers provoke an opportunity attack? This hasn't been challenged, but I would say this is definitively answered by the rules. The only exceptions for provoking opportunity by moving out of range are for the disengage action, teleporting, and being moved by someone or something without using a movement, action, or reaction to do so. Dissonant whispers requires the use of a reaction, so it is not exempt from provoking.
2. Can booming blade be used with warcaster for an opportunity attack? This is the debated topic, but it seems like the answer is yes because booming blade requires you to make a melee attack on a creature within range, which satisfies the condition that the spell must be cast "at" a creature.
3. Does the movement from dissonant whispers trigger the thunder damage? The problem here is the interpretation of willing movement. I interpreted this as identical to the criteria for opportunity attacks, but I can see the other side. It may be a DM discretion issue then, but it's not terribly impactful either way on the combo since they would still trigger the damage when they move toward you on their turn.
Anything not discussed or overlooked can still be valuable to this discourse, and I thank you all for your input.
Tarodnet, please stop posting incorrect information about this spell. You've been corrected multiple times now.
The Sage Advice on this topic that you keep referring to had the same wording at least as far back as September 2017 according to the Wayback Machine. As I already mentioned a couple of times in this thread, the Booming Blade spell had official errata which drastically changed the spell in the SCAG errata of 2020. So, any developer comments which may have been published before that time are completely obsolete.
The notation for the Range and Area parameters of every spell has a specific meaning. Whenever you see the exact notation of "Range: AAA (BBB)" the "AAA" always refers to the range of the spell and the "BBB" always indicates that the spell is an AOE spell with the AOE's size and shape specified there. Please do not confuse other readers by suggesting that maybe sometimes this notation actually could mean something else. It cannot. There are hundreds upon hundreds of officially published spells in the game and in every single case where you see the above notation it means exactly as I've described above. Every time. Even the developer comment posted earlier by plaguescarred gets it right:
As for your specific comments:
NOOOOOO!!!!! It absolutely does NOT mean this! This notation NEVER means this! See above. The range is "self". The size and shape of the AOE is "5-foot radius" (sphere implied).
WRONG! It appears right there in the spell parameters! AND it appears in the first sentence of the spell description! The spell is quite literally creating an AOE with a specific effect that is triggered in a specific way. As soon as the spell is cast it creates an AOE for the duration.
NO. There is nothing first about it. You are making up words that are not there. The reason why the spell says that you suffer the weapon's normal effects and then you suffer the effects of the AOE is because that is literally how all AOE spells work when their effects need to be triggered. The triggering event occurs, and then the AOE (WHICH IS ALREADY THERE) affects the appropriate creature. For example, there are dozens of spells that say something like "when a creature enters the area or begins its turn there, [then] something happens". You don't say, the AOE causes damage to the creature and then the creature moves into the area. That would make no sense. The AOE is already there, a trigger occurs (such as entering the area) and then something happens to the creature.
Ok, you really need to stop saying this. Any reference to 5 feet is NOT the range of this spell. That is incorrect information, and you are confusing readers with this. The range of this spell is "self".
It's unclear even what you are trying to say here, but this is absolutely NOT how this spell works at all.
This is incorrect, but at least it's a more reasonable mistake. The AOE is already there. It's created by the spell and specified by the spell parameters. If you miss, you just cannot trigger anything that actually affects a creature that is located within the AOE. But the AOE is there, it just doesn't do anything to the creature.
This short piece of fiction is actually completely wrong twice, impressively enough.
First, this reference to 5 feet is NOT the range of the spell! This has nothing to do with the range of the spell! And we know that this cannot be the range of the spell because the range of the spell is "self"! You cannot be 5 feet away from yourself!
Second, this reference to 5 feet doesn't even have anything to do with that OTHER reference to 5 feet! They are totally unrelated! They happen to be using the same number by sheer coincidence. This reference to 5 feet is only talking about what happens to the affected creature if it moves this far before the start of your next turn. The creature does NOT even need to be moving outside of the AOE for this to trigger. It could be just circling around you but remaining close to you and it would still trigger this effect. It's literally just referring to distance travelled, not related at all to potentially crossing any sort of geographic boundary or anything of that sort. And definitely NOT related even one iota to the range of the spell.
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Look, I've already gone into plenty of detail and have provided all of the information for how this spell works. Use the information however you wish.
The entire argument here breaks down to a disagreement on what is meant by the word target (or more specifically Self(X radius) .. and what is considered the target of the booming blade cantrip) within D&D 5e and it is clear (due to several examples of different usages) that this is not well defined (target is semantically used in the rules for both the point in space that is the source of an AoE and the creatures affected by an AoE).
Stating that someone's interpretation is incorrect because you arbitrarily decide that some of the examples contained in RAW are "erroneous" in your opinion and then state someone else is wrong because they don't go along with your arbitrary revisions of RAW to match your preferred interpretation is just a logical fallacy. Both interpretations are possible for what the word "target" means within 5e.
This is why the game has and needs a DM to decide how these mechanics will be run in their game. It is also why there are several arguments out there (what a target IS, is just one of them) that have been discussed many times over the years with two or more positions on how the rules should be interpreted. Until those rules are officially updated or errata'ed, there is no way to state which of these positions is the "correct" one in terms of RAW since the terms involved (like "target") are not sufficiently well defined or may be used in multiple valid contexts within the rules.
EDIT (I hadn't interpreted the spell correctly at the moment of writing this. In my opinion, Booming Blade doesn't create an AoE)
That's absolutely true, butBooming Blade has a different description in its spell entry when you compare with an AoE spells. In my opinion,the AoE is not created if you don't hit the targetBooming Blade doesn't create an AoE. You have a different opinion, and that's okay. Cone of Cold or Burning Hands describes the area of effect. Fireball describes the area. Or Ice Knife. Booming Blade doesn't, or not clearly to me.In fact, what's the affected area really? The creature or your surroundings? It seems to be only the creature: "and then becomes sheathed in booming energy". My understanding, again.
The description of the spell:
Only two more things:
(emphasis mine) Where in the text is that mentioned?
The first sentence is: "You brandish the weapon used in the spell's casting and make a melee attack" So the first thing to do is a melee attack.
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@up2ng, I agree with you about what Self (X' radius, line, etc.) means. The original post is about using Booming Blade when a creature triggers the opportunity attack, anyway.
I will edit my previous answer to remove some parts, as I used the 5 ft. value to explain myself, but it had the opposite effect. Sorry for the confusion.
So after looking into this, I find many aspects of this line of argument are immaterial. The main point of contention here is whether booming blade works with war caster. The requirement for this is that the spell is cast at the creature provoking, casting time is one action, and the spell must target only that creature.
The main argument is that booming blade targets self, not the creature. This is based on the range which is Self (5-foot radius). I find this is not correct. If exclude booming blade and green flame blade (since they're both similar and the spells we're debating), there are no spells with this range that target self. One example, thunderclap is an AOE that is centered around the caster but notably does not target the caster. It targets the area around the caster excluding the caster from the AOE. So based on the range, the spell does not target the caster in any case where this range is used.
So then we ask about AOE. There has been debate on whether AOE spells target the affected creatures, but I don't think it matters because it doesn't seem booming blade actually has an AOE. Looking at the details of the spell, what does it say? Firstly, it says You brandish the weapon used in the spell’s casting and make a melee attack with it against one creature within 5 feet of you. This clearly seems to be the requisite actions for casing the spell as is the norm for many spell descriptions. This means none of this is part of the spell's effect, which makes sense since none of it is magical. Next we have On a hit, the target suffers the weapon attack’s normal effects and then becomes sheathed in booming energy until the start of your next turn. If the target willingly moves 5 feet or more before then, the target takes 1d8 thunder damage, and the spell ends. So now we have effects of the spell, but who is affected? The target of the attack is the only creature affected.
Given only one creature is affected by the spell, it seems quite clear that the spell is single targeted at the creature being attacked. The range describes self being the center point of the spell and 5ft being the potential range of the spell's effect, which is to sheath a creature with booming energy. Given this interpretation, it seems clear that the booming blade does work with war caster. If we assume the target of the spell is self, then we have the absurdity that the target of the spell is not at all affected by the spell effect upon success. What other example of a spell is there where the spell target isn't affected by the effect of a spell?
The main problem with this approach is spells like Spirit Guardians that use the same wording for range as Booming Blade. Spirit Guardians is a spell with range Self (15' radius) which does not use the word "target" to describe the creatures affected by the spell. In the case of casting Spirit Guardians, I don't think there are many that would argue that the spellcaster is not the target of the spell (who is not affected unless the caster decides they want to be).
The problem is that Booming Blade uses the same terminology in describing the range of the spell as Self (5' radius) potentially implying that the spellcaster is the target. On the other hand, Booming Blade also explicitly calls the creature affected by the "energy" as the target of the spell "On a hit, the target suffers the weapon attack’s normal effects and then becomes sheathed in booming energy until the start of your next turn."
The specific clause of War Caster states:
"When a hostile creature's movement provokes an opportunity attack from you, you can use your reaction to cast a spell at the creature, rather than making an opportunity attack. The spell must have a casting time of 1 action and must target only that creature."
So, as mentioned earlier in the thread ... the entire argument devolves to what is the target of the spell. Target is used to both define the point the spell is aimed at AND creatures affected by the spell depending on what part of the rule book you read. In the case of Booming Blade, I rule that the target of the spell is the creature being attacked by the melee weapon used in the spell. This makes Booming Blade usable with War Caster when I am running the game but I am not going to say other interpretations (that rely on different interpretations of what a target for the spell is) are wrong.
I suppose Spirit Guardians does seem to pose a little quandary. Many would suppose that the caster is affected when it says "They flit around you to a distance of 15 feet for the duration." Arguably you could say that the caster is not a target, but the area around him is.
But even so it seems to me that booming blade still doesn't target the caster because there is no effect of the spell which affects the caster. And while Spirit Guardians explicitly affects an area, booming blade does not. Booming Blade merely affects the target of the attack, which is why I think the attack target is the sole target of the spell. Any other target would have to at least be affected by the spell, but there is no one other than the attacked creature. On this point we seem to be in agreement. While you may argue that affected creatures are necessarily spell targets, I argue that at least any target of the spell must be affected upon success. The caster is not affected, so he's not a target.
You're correct that it doesn't target the caster. "Self" and "Self (Xft radius/cone)" are different, that's why they're written differently. "Self" targets the caster, "Self (Xft radius/cone/etc.)" targets an area or creatures in an area defined by the phrase in parenthesis and an origin of the caster. In the case of Booming Blade the caster is defined as the origin and "(5 ft radius)" defines an area around the origin from which you choose a creature to target with a melee attack. In other words: booming blade targets a single creature within 5 feet of the caster. Greenflame Blade may or may not target "only that creature" within 5 feet of the caster, depending on what you choose for the secondary target. (Note: a "spell that targets only that creature" is not necessarily a "spell with a single target", so when you choose the initial creature to receive the secondary damage of GFB, it does NOT have a single target but it does target only that creature.)
Another spell that illustrates this is Prismatic Spray, a spell with "Range/Area: Self (60 ft cone)": https://www.dndbeyond.com/spells/2214-prismatic-spray (quoted is the most up-to-date text of the spell)
Like with booming blade, the targets are one or more creatures within the defined area, written in the spells range as "Self (60 ft )", that is, one or more creatures within a 60ft cone originating from the caster. This agrees with the previous post: the caster is not considered a target when the word "Self" in the range is followed by parenthesis; the target is instead the defined area or something(s) within it.
Thank you for the input. Debate here has focused on whether booming blade works with War Caster. But if we take for granted that it does, there seem to be no other objections to the combo. You can use dissonant whispers in melee range to cause opportunity attack and use booming blade for that attack (with War Caster assuming it works) to do the spell damage and weapon damage. There's question on whether it triggers the thunder damage right away, but even if it doesn't it's active on their next turn. Seems to me like a really good combo for a first level spell and cantrip.
Booming Blade and Green-Flame Blade are strange beasts, to be honest. That was one of the things I had in mind when I wrote my opinion about how Booming Blade works, but I think I failed miserably.
Thanks for the latest post about the difference between the two kinds of Self ranges.
In case you're interested, I bookmarked this post from Reddit some time ago, and it has a good explanation about this matter: Spells w/ Range of Self, Rules Clarification
So I wanted to bring up a consideration I thought of with the Thunder damage aspect here. This damage requires willing movement of at least 5 feet to trigger. This was briefly addressed by some to say the movement caused by the spell doesn't qualify as willing movement presumably because the creature doesn't choose to move.
One thing I wanted to bring up was the extra dimension of meta vs in game choices. It seems to me that the spell here only takes the creature's choice to move away from a meta game perspective. Dissonant whispers isn't a mind control spell. It essentially produces a sound that only the target hears which is so painful they instinctively react by moving away from it. This would be akin to getting stung by bees and instinctively running away from it. The point is it doesn't necessarily mean they didn't "willingly" move away in game. They just had such a compelling reason to move they couldn't consider it.
Now personally I think the spell should have the same criteria for willing movement as what is listed for opportunity attacks. With this, the fact that their reaction was used to move would be sufficient to trigger the damage. To suggest that a choice is needed suggests the booming energy is considering the psychological state of the subject for its trigger, which seems absurd. But what seems even more absurd is that the booming energy is actual considering the presence of a metagame choice available to the player or DM as a condition for the trigger.
So I thought this might be an important point of consideration. Does the spell compell movement for the character or the player? Does the spell consider the psychology of the character? Does it even further consider the metagame choices available? These are important implications for the role playing game. Potentially the metagame considerations would break emersion, which is an important aspect of the game.
Literally the second post in this thread refutes the idea that dissonant whispers creates willing movement
Active characters:
Carric Aquissar, elven wannabe artist in his deconstructionist period (Archfey warlock)
Lan Kidogo, mapach archaeologist and treasure hunter (Knowledge cleric)
Mardan Ferres, elven private investigator obsessed with that one unsolved murder (Assassin rogue)
Xhekhetiel, halfling survivor of a Betrayer Gods cult (Runechild sorcerer/fighter)
That's the problem I pointed out. Does it make sense that the spell has meta world detection for consideration of the trigger for damage?
I addressed that later in the post you quoted.
As you can see there is a huge discussion on what is possible here. So my advise would be to ask your DM cause he has the final say anyway.
Attack: [roll]3d20dl2+6[/roll] Damage: [roll](if([roll:-1:critical], =0, 1d8, 2{1d8}.expand()))+4[/roll] Sneakattack: [roll](if([roll:-2:critical], =0, 2d6, 2{2d6}.expand()))[/roll]