Unless a feature says that it doesn't use movement, moving always costs movement... What you are thinking of is that you do not provoke Opportunity Attacks when moving withina creature's reach.
And if they decided to stop moving once they got hit then they wouldn't be out of your reach meaning you couldnt get an attack of OP anyway.. and as the rule states you're hitting them WHILE they're moving out of your reach so they're still moving when the bb is applied the 2nd time and should cause it to go off again.
As has been stated clearly multiple times now, there is no paradox of causation. OAs are not provoked by a creature actually moving a set amount of distance; they are provoked by a creature in the process of moving away from an enemy creature without the proper use of the Disengage action. An OA is provoked while each creature is still in their original positions. An OA is executed while each creature is still in their original positions. The typical result of completing an OA is that the provoking creature continues their turn by crossing into the next square. They don't necessarily have to continue moving, and it does not create a chronological paradox if they don't keep moving.
I think the bar--for either a DM or player--to make the decision to not keep moving after taking an OA must be very high, but not impossible. The rationale for a creature to knowingly do something dangerous (provoking an OA), and then changing their mind after suffering the consequences (but not the reward) of their decision needs to believable. It's a roleplaying game after all.
I agree with this. 5e design philosophy is terribly bi-polar. We've got so many aspects of the actual game system that are written with broad strokes. Simple writing is great, and writing things in a way that the average person can follow is also great... if it's consistent. Movement, movement in combat, and movement-triggered effects are (IMO) the worst offenders. It's one of the most important foundational sections, yet it's also the most vague. There are so many spells/abilities/features that depend on absurdly-specific movement scenarios that are not ever defined in the basic rules they purport to depend on.
I think one of the reasons they avoid talking about movement triggers as explicitly 5ft, 10ft, etc is because 'Theater of the Mind' is still a common thing for a lot of groups, and there's nothing in the rules mandating that movement only be in 5ft chunks. The smallest increment of movement I've seen the books reference is 1 foot, but that's not a mandated increment either. The designers really need to understand that while simplicity and intentional vagueness can be good things, the entire product needs to be contained within a cohesive tier of granularity. If they want to have the rules on movement be relatively vague, they can't have other things rely on an aspect of those rules which are not defined.
Which comes back to one of your questions... if a creature is already under the effect of BB, decides to run & provoke an OA (which the enemy will use to cast BB again), does the original BB trigger before the OA? Yes. If they begin to move away from an enemy in melee range, prior to provoking the OA, they've moved. Even if it's just 1 foot of movement within the same square. Boom. Nobody can argue with that. They keep moving to the edge of their square to leave the other creature's reach. They trigger an OA from the enemy creature, and that creature casts BB again. The creature decides to keep moving out of the enemy's reach. Boom again.
my dm argues that since bb spell says movement and he says dnd defines movement as 5ft than it wouldn't go off until he was already out of my reach but i could still get the attack of op but it wouldn't double stack the spell. He said that 1-4ft of movement isn't a thing and can't go off unless he moves past the 5ft marker
Which is completely within their prerogative, and part of the reason that I brought it up. I don't think it's necessarily anymore correct than Sigred's read (I actually agree more with Sigred's read), but acknowledging that it's in that gray area for people in general helps others prepare for the possibility. As far as the movement is concerned, the movement section has the number 5 in it twice: once mentioning chapter 5 equipment and once mentioning a -5 penalty to passive Wisdom (perception) scores when traveling at a fast pace. There is no official 5 ft definition for D&D. This is due to the fact that Theater of the Mind is a valid option. The 5 ft thing comes from the common method of playing on maps with a defined 5 ft square, but you could just as easily play with a different value. 5 ft works well for reach and the common speeds are all divisible by 5.
From the DMG (I believe it was combat section):
The most common unit for tactical maps is the 5-foot square, and maps with grids are readily available and easy to create. However, you don’t have to use a grid at all. You can track distances with a tape measure, string, craft sticks, or pipe cleaners cut to specific lengths. Another option is a play surface covered by 1-inch hexagons (often called hexes), which combines the easy counting of a grid with the more flexible movement of using no grid. Dungeon corridors with straight walls and right angles don’t map easily onto hexes, though.
Thus, your DM has defined movement as 5 ft through interpretation. If that is how they are going to rule, that's fine as long as it's consistent and it helps everyone have fun by speeding things along.
I am glad that I found this thread and that it has been going on for over year and a half, as I am definitely going to get War Caster on my Divine Soul Sorcadin with Booming Blade, and I wanted to find out what kind of combos I can do with these... what I was surprised to see is that none of the people commenting actually mentioned some very important wordings on Opportunity Attacks and War Caster, and really disliked how Stormknight not only ignored the very first sentence for opportunity attacks, but also removed important part of the last sentence, so I will try to explain how I currently understand this situation RAW and RAI
Booming Blade
As part of the action used to cast this spell, you must make a melee attack with a weapon against one creature within the spell's range, otherwise the spell fails. On a hit, the target suffers the attack's normal effects, and it becomes sheathed in booming energy until the start of your next turn. If the target willingly moves before then, it immediately takes 1d8 thunder damage, and the spell ends.
from this it's more than obvious that the creature IMMEDIATELY takes the secondary damage when it willingly moves - therefore as soon as itstarts moving, and if this damage would kill it, it's corpse would stay on the square it started it's movement on
War Caster (PHB 170)
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 opportunityattack. The spell must have a casting time of 1 action and must target only that creature.
based on the first sentence; instead of taking Opportunity Attack reaction, you are essentially taking Cast a Spell reaction, which invalidatesOpportunity Attack and it's behavior, and the reaction should, in fact, behave according to the Cast a Spell action, HOWEVER; according to Crawford, the spell cast has the same timing as the Opportunity Attack, thus we have to look for the timing in OA rules to determine when the Cast a Spell takes part
Opportunity Attack (PHB 195)
You can make an opportunity attack when a hostile creature that you can see moves out of your reach. To make the opportunity attack, you use your reaction to make one melee attack against the provoking creature. The attack interrupts the provoking creature’s movement, occurring right before the creature leaves your reach.
First sentence states that the OA triggers when a creature moves out of the reach, therefore it's crucial for the creature to actually start moving, and therefore it is not possible for the creature to decide that it wants to stay in place after OA, [just a clarification, as this has been mentioned several times]... Now, as I said before, I was surprised that no-one here mentioned the movement interruption during OA, which is, in my opinion, really crucial to this: the creature has decided to and already started to move, the movement got interrupted right before leaving your reach,at this point in time, the creature is still in your reach, but the movement has already begun, and that's when you cast your spell and hit it with Booming Blade. The creature then has to continue to move, it CAN NOT decide to stop moving mid-movement, as the interruption was not voluntary... essentially, the movement was already decided upon, and part of it already occurred, as it triggered OA, otherwise it would not trigger it, but it got interruptedright before leaving reach by the OA timing, thus the Booming Blade was casted after the creature started moving, but before leaving reach, which means the creature will continue moving when you hit it with a weapon, and therefore should immediately take the secondary damage
however what I am more interested in is what happens if the creature already has a Booming Blade effect on it... based on my own emphasis above, and how I understand RAW:
The creature has a Booming Blade effect on itself and decides to move away; because it has already started the movement [which is essential to trigger OA], the Booming Blade effect should trigger and damage the enemy [as mentioned before, Booming Blade damages the enemy immediately, and if the damage would kill the creature, it would stay on it's original square as the damage and subsequent death would interrupt the movement]. If the creature survives secondary BB damage, then it is still moving out of your reach, thus it triggers your OA, which allows you to cast Booming Blade, and it's secondary damage should trigger again because the OA timing was mid-movement, and the creature continued moving when it got hit.
Since we established the timing of OA, and there has been mentioned Sentinel feat several times I decided to give it a go as well
When you hit a creature with an opportunity attack, the creature's speed becomes 0 for the rest of the turn.
Again, based on when OA occurs we can clearly see that the movement started, it triggered OA, which interrupted the movement, and the sentinel then drained it's movement speed, thus the creature could not resume movement, which I understand would work similarly as if the creature would die from Booming Blade's secondary damage.
As I said, no one in this 1.5 years long thread mentioned the movement interruption, and this is how I understood RAW. I would love to hear your feedback on this, as this is how I would rule it in my games.
I also realize that the double Booming Blade proc seems rather OP, but RAW that's how I see it. However since the first sentence in OA states that you can make OA after the creature moves out of your reach, and not starts to move out of your reach, even tho the attack takes place before it leaves your reach, the wording could be interpreted as that the OA is triggered after the movement is done, but it actually [somehow, magically] takes place before the creature actually leaves your reach, just so it makes sense mechanically - so you can actually hit it [otherwise it would be too far], and to clarify where the dead body would end up. Thus RAI you could rule that the Booming Blade's secondary damage from Opportunity Attack would trigger only if the creature would move again after moving out of reach. And so to answer the original question of the thread:
RAW: 3) wreathed in booming energy 5 feet away, but already moving, so triggers extra damage immediately
RAI: 2) wreathed in booming energy 10 feet away and chooses whether or not to continue moving
Of course everyone open to play this as they like, but the key wording for our game is “when a hostile creature that you can see moves out of reach”. To me this means the attack happens when the target is in the next square/hex as opposed to the threatened square/hex. (Ie the precise moment it leaves that square/hex is the moment it “moves out of reach”). The creature might then (if it realises what happening to it) choose to stop in its tracks — thus avoiding the damage from voluntarily moving.
Agree w SEnergy that it would be a pretty sweet double banger (and more at higher levels) to get a BB in place on your turn and then follow it up with another via War Caster as they move away! (At 5th lvl and higher: BANG on hit when you cast BB as an action on your turn. BANG when it moves at the start of its turn. BANG when you cast it via Warcaster as it moves out of reach. And then BANG for a fourth time if it continues its movement...
(Note - the above intentionally avoids the complication of the attack happening “right before the creature leaves your reach” as we play on a grid and maintain that creatures move in a discreet fashion from one square/hex to the next, not a continuous motion. The attempt to avoid a discussion about limits and the infinitesimally small amount of the creature remaining in the threatened square ... hmmm ... not quite as successful as I’d have liked).
RAI: 2) wreathed in booming energy 10 feet away and chooses whether or not to continue moving
Senergy,
I would contest this one point; booming blade has a range of 5ft and therefore was not RAI to wreath an opponent 10ft away.
Cheers!
I would contest your contestation, it has been consistently argued that with Polearm Master an enemy triggers the AoO at the edge of range/ square before range.
So with Polearm Master and a Spear, they enemy would be hit and stay at 10ft range, that is because starting to move starts the AoO, and then is finished before the person actually moves
Rollback Post to RevisionRollBack
D&D, Youth Work and the Priesthood sadly do not typically interact... I do what I can!
RAI: 2) wreathed in booming energy 10 feet away and chooses whether or not to continue moving
Senergy,
I would contest this one point; booming blade has a range of 5ft and therefore was not RAI to wreath an opponent 10ft away.
Cheers!
that would, however, negate basic OA in the first place, as the reach of most weapons is only 5ft as well...
what I meant by RAI was that the attack actually happens while the creature is within reach, but since it's a grid and creatures do not move continuously, but rather sort of 'teleport', the movement is [and has to be] already completed when they trigger OA [first sentence of OA], and since the movement is completed already and creature is out of reach, the booming blade [which actually happened before it left reach] somehow happened after it left, but at the same time happened before it left... thus becoming wreathed in booming energy 10 feet away and chooses whether or not to continue moving... the RAI, however, sort of ignores the movement interruption, which I believe is really important
again, first and last sentences of OA say that you can make an OA after the creature leaves your reach [the movement is completed], but actually happens before it leaves your reach... thus it somehow occupies both spaces at the same time, but RAW I'd rule that the movement is not completed, but rather somehow paused, as it clearly states that it interrupts it, and creature has only begun to move
However since the first sentence in OA states that you can make OA after the creature moves out of your reach, and not starts to move out of your reach, even tho the attack takes place before it leaves your reach, the wording could be interpreted as that the OA is triggered after the movement is done, but it actually [somehow, magically] takes place before the creature actually leaves your reach, just so it makes sense mechanically - so you can actually hit it [otherwise it would be too far], and to clarify where the dead body would end up. Thus RAI you could rule that the Booming Blade's secondary damage from Opportunity Attack would trigger only if the creature would move again after moving out of reach
I think WotC should re-word the first sentence of OA to: You can make an opportunity attack when a hostile creature that you can see attempts to/starts to move out of your reach, which would definitely clarify that the attack happens before arriving on the next square in the grid/leaves your reach, but the current wording implies some sort of state of quantum superposition of the creature being both within and out of the reach
basically it comes down to how you interpret the movement interruption I guess... however the more I try to explain it the more I myself get confused and start to disagree with my own RAI and lean more towards RAW ruling, where the secondary booming blade effect triggers right after OA, as part of the same movement that triggered OA
I am not looking for a deep dive here, just saying booming blade does not wreath an opponent in energy, at 10ft away, under any other circumstances. e.g. a reach weapon cannot be used to deliver the spell to a target 10 ft away. So my argument is... if there is a RAW against it, then it is not reasonable to assume that wizards intended to negate that rule under a particular circumstance.
Of course, it doesn't really matter, the rule is unclear that's why this thread is still active.
As for polearm master, cheeky_hamster, those rules are written. And I dare say petty clear, but not particularly relevant to booming blade - warcaster issue being discussed here. IMO
I am not aware of any written rules concerning the interaction of Booming Blade and Warcaster, Pole Arm Master, or even opportunity attacks. RAW is ambiguous. We are left to make inferences from RAI guidance as well as other written general and specific rules whose application (or lack of) to the situation are fair game for seven pages and a year and half worth of discussion.
It's already in the sage advice that in order to use booming blade/ green flame blade with a 10ft reach weapon you must also have the spell sniper feat.
My understanding is that OA is interrupting the turn, not the action. OA clearly states the attack occurs as a result of the movement but retroactively takes place for the sake of melee reach mechanics.
If compared to another Wizard of the Coast product... We would resolve the stack in reverse order.
I.E. Movement is the effect on the stack, triggers the passive ability on the board > OA, OA goes onto the stack, Replacement effect Battle Caster may be chosen
Resolve Battle Caster, resolve movement action, BB secondary effect goes on the stack, resolve secondary effect, priority returns to the active character.
This discussion really seems like an awful lot of huffing and puffing over a single d8 of damage that a DM doesn't want to let happen. Sure there could be a situation where someone uses their own reaction to counter the spell or a reaction to redirect the attack as per various spell or class features.
Sentinal is a fairly poor comparison as it has specific wording that allows it to stop the possibility of moving retroactively in addition to the retroactive interruption that is the OA reaction.
That said, DM's word is always law. Literal interpretations to the wind on a whim.
Afterthought.. Even if the creature is aware of the effect and has the option of stopping, it is fairly likely to not be dissuaded by that d8 of Boom unless it was potentially fatal or they found it personally quite irritating.
Any ruling is fine by me as long as: if it works for the player it works for the DM and Vice Versa.
My understanding is that OA is interrupting the turn, not the action. OA clearly states the attack occurs as a result of the movement but retroactively takes place for the sake of melee reach mechanics.
If compared to another Wizard of the Coast product... We would resolve the stack in reverse order.
I.E. Movement is the effect on the stack, triggers the passive ability on the board > OA, OA goes onto the stack, Replacement effect Battle Caster may be chosen
Resolve Battle Caster, resolve movement action, BB secondary effect goes on the stack, resolve secondary effect, priority returns to the active character.
This discussion really seems like an awful lot of huffing and puffing over a single d8 of damage that a DM doesn't want to let happen. Sure there could be a situation where someone uses their own reaction to counter the spell or a reaction to redirect the attack as per various spell or class features.
Sentinal is a fairly poor comparison as it has specific wording that allows it to stop the possibility of moving retroactively in addition to the retroactive interruption that is the OA reaction.
That said, DM's word is always law. Literal interpretations to the wind on a whim.
Afterthought.. Even if the creature is aware of the effect and has the option of stopping, it is fairly likely to not be dissuaded by that d8 of Boom unless it was potentially fatal or they found it personally quite irritating.
Any ruling is fine by me as long as: if it works for the player it works for the DM and Vice Versa.
The damage of Booming Blade does scale, so it's not always a single d8. If we that a d6 weapon was used to apply Booming Blade (purely for damage differentiation), you would have the 1d6+melee attack stat modifier + the "single d8" after voluntary movement. At fifth, that goes to 1d6 + attack mod + 1d8 on the attack + 2d8 voluntary movement trigger damage. 11th goes to 1d6 + attack mod + 2d8 + 3d8 on trigger and 17th 1d6 + attack mod + 3d8 + 4d8 on trigger. It's not groundbreaking at all, but it's stronger if the triggered damage is always present. It also stacks with hex/hunters mark, sneak attack, Great Weapon Master, and similar buffs to melee attacks and the non triggered damage is increased by crits. Not all of these stack with each other and some stack with other spell attacks, but there are some balance concerns involved that can leave party members feeling a little left behind.
The damage of Booming Blade does scale, so it's not always a single d8. If we that a d6 weapon was used to apply Booming Blade (purely for damage differentiation), you would have the 1d6+melee attack stat modifier + the "single d8" after voluntary movement. At fifth, that goes to 1d6 + attack mod + 1d8 on the attack + 2d8 voluntary movement trigger damage. 11th goes to 1d6 + attack mod + 2d8 + 3d8 on trigger and 17th 1d6 + attack mod + 3d8 + 4d8 on trigger. It's not groundbreaking at all, but it's stronger if the triggered damage is always present. It also stacks with hex/hunters mark, sneak attack, Great Weapon Master, and similar buffs to melee attacks and the non triggered damage is increased by crits. Not all of these stack with each other and some stack with other spell attacks, but there are some balance concerns involved that can leave party members feeling a little left behind.
Ah, indeed it does scale. In term of Roleplay though I'd be inclined to compare it to walking into a trap. You wouldn't let a player take back a move because they stepped on a trigger plate and took damage, right? Why would you have an NPC take back the move for the very same reason? Give the RP reason at table to justify why the spell isn't working as it mechanically should. I don't think you need dice rolls but it might make it more palatable. Or is the NPC so critically important to the plot that the players choosing to kill the thing they are fighting/deciding to fight is a big nono?
In what way is them downing a single NPC so game breaking? "They did too much damage" is the same justification used to homebrew nerf Smites and Sneak attacks. But it is still homebrew. "But my game balance!" Still homebrew.
There are several steps prior to the fight where the DM could have disallowed the combination. Feats are optional Rules content. Multi-classing is optional Rules content. Let the Gish have the one thing they do sorta ok?
The damage of Booming Blade does scale, so it's not always a single d8. If we that a d6 weapon was used to apply Booming Blade (purely for damage differentiation), you would have the 1d6+melee attack stat modifier + the "single d8" after voluntary movement. At fifth, that goes to 1d6 + attack mod + 1d8 on the attack + 2d8 voluntary movement trigger damage. 11th goes to 1d6 + attack mod + 2d8 + 3d8 on trigger and 17th 1d6 + attack mod + 3d8 + 4d8 on trigger. It's not groundbreaking at all, but it's stronger if the triggered damage is always present. It also stacks with hex/hunters mark, sneak attack, Great Weapon Master, and similar buffs to melee attacks and the non triggered damage is increased by crits. Not all of these stack with each other and some stack with other spell attacks, but there are some balance concerns involved that can leave party members feeling a little left behind.
Ah, indeed it does scale. In term of Roleplay though I'd be inclined to compare it to walking into a trap. You wouldn't let a player take back a move because they stepped on a trigger plate and took damage, right? Why would you have an NPC take back the move for the very same reason? Give the RP reason at table to justify why the spell isn't working as it mechanically should. I don't think you need dice rolls but it might make it more palatable. Or is the NPC so critically important to the plot that the players choosing to kill the thing they are fighting/deciding to fight is a big nono?
In what way is them downing a single NPC so game breaking? "They did too much damage" is the same justification used to homebrew nerf Smites and Sneak attacks. But it is still homebrew. "But my game balance!" Still homebrew.
There are several steps prior to the fight where the DM could have disallowed the combination. Feats are optional Rules content. Multi-classing is optional Rules content. Let the Gish have the one thing they do sorta ok?
Using your trap analogy, if the trap was a pressure plate that the release of the plate caused the damage, would force the Player or the NPC to step off the plate because they stepped on in? Sure, they voluntarily stepped on the plate but some people would stop upon hearing the click (assuming that momentum didn't carry them forward, and then they'd be cringing that they didn't stop) and others would try to immediately move to clear. Depending on the nature of the trap and the knowledge of the creature, taking damage such as a nail on the plate or a dart launched at them to encourage them to move might encourage them to change their mind either way.
I'm not saying that I would do it all the time, but I don't think that it should be a case of automatic full damage.
In term of Roleplay though I'd be inclined to compare it to walking into a trap. You wouldn't let a player take back a move because they stepped on a trigger plate and took damage, right? Why would you have an NPC take back the move for the very same reason? Give the RP reason at table to justify why the spell isn't working as it mechanically should. I don't think you need dice rolls but it might make it more palatable. Or is the NPC so critically important to the plot that the players choosing to kill the thing they are fighting/deciding to fight is a big nono?
In what way is them downing a single NPC so game breaking? "They did too much damage" is the same justification used to homebrew nerf Smites and Sneak attacks. But it is still homebrew. "But my game balance!" Still homebrew.
There are several steps prior to the fight where the DM could have disallowed the combination. Feats are optional Rules content. Multi-classing is optional Rules content. Let the Gish have the one thing they do sorta ok?
You seem intent on misrepresenting the argument. The argument is that neither Booming Blade nor the Opportunity Attack mechanics explicitly state, nor imply, that a target of either must keep moving after being hit with either. The argument is not "that is too powerful and should be disallowed", nor "that is not overpowered, and should be allowed", nor is it "as a DM, I would really like my NPC to stay alive, so I'm not allowing it", nor "as a player, I'd like to dispatch enemies faster, so it should be allowed", nor is it "as a DM, I want to disallow that combination, so I'm claiming the rules forbid it", nor anything of the sort. Moreover, the discussion is not about game balance or individual preference, but -- as appropriate to this sub-forum -- about game mechanics, "Rules as Written". Going by that, there is no blanket prohibition on a target of Booming Blade stopping upon being hit with the spell, even if hit mid-movement. The rules allow targets to move as far as they desire, as long as they respect their speed, and to stop whenever they desire, for whatever reasons they desire. The rules do not force players to commit to a course of action once "declared" (you can even back out of a Readied Action, although you lose your Reaction by doing so). In fact, even if the rules did force character to keep moving after being hit with the spell, an Opportunity Attack, or both (via War Caster, although strictly speaking, that's not an Opportunity Attack, but rather a spell cast using your Reaction instead of an Opportunity Attack), the target would still not take the extra damage. The extra damage is triggered by willing movement. If the target does not have the option not to move, then it is not willing movement. The only argument I can see, within the rules as written, is "if the target is unaware of Booming Blade's effects, they have no logical reason for stopping their movement", which is a valid argument. Whether it's correct or not depends on the DM's interpretation of the spell's description; on whether the spell's "booming energy" that "sheathes" the target is enough to indicate, or at least suggest, that moving will cause extra damage to be taken.
You seem intent on misrepresenting the argument. The argument is that neither Booming Blade nor the Opportunity Attack mechanics explicitly state, nor imply, that a target of either must keep moving after being hit with either. The argument is not "that is too powerful and should be disallowed", nor "that is not overpowered, and should be allowed", nor is it "as a DM, I would really like my NPC to stay alive, so I'm not allowing it", nor "as a player, I'd like to dispatch enemies faster, so it should be allowed", nor is it "as a DM, I want to disallow that combination, so I'm claiming the rules forbid it", nor anything of the sort. Moreover, the discussion is not about game balance or individual preference, but -- as appropriate to this sub-forum -- about game mechanics, "Rules as Written". Going by that, there is no blanket prohibition on a target of Booming Blade stopping upon being hit with the spell, even if hit mid-movement. The rules allow targets to move as far as they desire, as long as they respect their speed, and to stop whenever they desire, for whatever reasons they desire. The rules do not force players to commit to a course of action once "declared" (you can even back out of a Readied Action, although you lose your Reaction by doing so). In fact, even if the rules did force character to keep moving after being hit with the spell, an Opportunity Attack, or both (via War Caster, although strictly speaking, that's not an Opportunity Attack, but rather a spell cast using your Reaction instead of an Opportunity Attack), the target would still not take the extra damage. The extra damage is triggered by willing movement. If the target does not have the option not to move, then it is not willing movement. The only argument I can see, within the rules as written, is "if the target is unaware of Booming Blade's effects, they have no logical reason for stopping their movement", which is a valid argument. Whether it's correct or not depends on the DM's interpretation of the spell's description; on whether the spell's "booming energy" that "sheathes" the target is enough to indicate, or at least suggest, that moving will cause extra damage to be taken.
Except it is right there in the OA, "You can make an opportunity attack when a hostile creature that you can see moves out of your reach." So, what is the creature doing? Hint, it's moving.
Sentinal has explicit wording that ceases the movement that is already in progress.
Booming Blade see's you going from tile A to tile B and says "hey, you get a boop for that", it does not stop the movement that is already in progress. It does not ask "are you sure you wanted to walk there?" It sees that you moved from one tile to another while under the effect and triggers.
You declared your move, that is willing movement. The fact that you didn't know the full consequences is moot.
I do find myself wondering if part of the communication issue is that I'm assuming everyone resolves movement one square at a time. I'm not suggesting you are forced to continue moving past the one tile it took to trigger the opportunity attack. I'm saying that the Booming Blade is applied in tile A where the Opportunity Attack is treated as hitting during the resolution of the OA, and that then it sees that you are now in tile B. Which is the tile you decided to move to voluntarily. Going from tile A to tile B being exactly the type on movement that triggers the secondary effect. Standing still or moving after that point is no longer a part of the discussion.
Using your trap analogy, if the trap was a pressure plate that the release of the plate caused the damage, would force the Player or the NPC to step off the plate because they stepped on in? Sure, they voluntarily stepped on the plate but some people would stop upon hearing the click (assuming that momentum didn't carry them forward, and then they'd be cringing that they didn't stop) and others would try to immediately move to clear. Depending on the nature of the trap and the knowledge of the creature, taking damage such as a nail on the plate or a dart launched at them to encourage them to move might encourage them to change their mind either way.
I'm not saying that I would do it all the time, but I don't think that it should be a case of automatic full damage.
Evasion/Danger Sense etc. Are what you are thinknig about there. Whether they keep moving or not after moving onto the square that triggered the trap is moot. What matters is that they DID move onto the trap. Just as they moved during the Opportunity Attack that trigger the Booming Blade. The movement happened, it isn't up to debate. If the was no movement there was no trigger. You are arguing in favor of taking a move back after finding out the result in an attempt to metagame.
Using your trap analogy, if the trap was a pressure plate that the release of the plate caused the damage, would force the Player or the NPC to step off the plate because they stepped on in? Sure, they voluntarily stepped on the plate but some people would stop upon hearing the click (assuming that momentum didn't carry them forward, and then they'd be cringing that they didn't stop) and others would try to immediately move to clear. Depending on the nature of the trap and the knowledge of the creature, taking damage such as a nail on the plate or a dart launched at them to encourage them to move might encourage them to change their mind either way.
I'm not saying that I would do it all the time, but I don't think that it should be a case of automatic full damage.
Evasion/Danger Sense etc. Are what you are thinknig about there. Whether they keep moving or not after moving onto the square that triggered the trap is moot. What matters is that they DID move onto the trap. Just as they moved during the Opportunity Attack that trigger the Booming Blade. The movement happened, it isn't up to debate. If the was no movement there was no trigger. You are arguing in favor of taking a move back after finding out the result in an attempt to metagame.
*Edited to be less hostile.*
I agree the person already made the choice to move which is why you got an attack of op in the first place you can't go back on that because of what war casted attack is placed on you. It happens in a split second so they wouldn't have time to react because they'd already be moving. I wish they'd actually release good sage advice on this ability because there's way to much left open for debate.
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my dm argues that since bb spell says movement and he says dnd defines movement as 5ft than it wouldn't go off until he was already out of my reach but i could still get the attack of op but it wouldn't double stack the spell. He said that 1-4ft of movement isn't a thing and can't go off unless he moves past the 5ft marker
Which is completely within their prerogative, and part of the reason that I brought it up. I don't think it's necessarily anymore correct than Sigred's read (I actually agree more with Sigred's read), but acknowledging that it's in that gray area for people in general helps others prepare for the possibility. As far as the movement is concerned, the movement section has the number 5 in it twice: once mentioning chapter 5 equipment and once mentioning a -5 penalty to passive Wisdom (perception) scores when traveling at a fast pace. There is no official 5 ft definition for D&D. This is due to the fact that Theater of the Mind is a valid option. The 5 ft thing comes from the common method of playing on maps with a defined 5 ft square, but you could just as easily play with a different value. 5 ft works well for reach and the common speeds are all divisible by 5.
From the DMG (I believe it was combat section):
The most common unit for tactical maps is the 5-foot square, and maps with grids are readily available and easy to create. However, you don’t have to use a grid at all. You can track distances with a tape measure, string, craft sticks, or pipe cleaners cut to specific lengths. Another option is a play surface covered by 1-inch hexagons (often called hexes), which combines the easy counting of a grid with the more flexible movement of using no grid. Dungeon corridors with straight walls and right angles don’t map easily onto hexes, though.
Thus, your DM has defined movement as 5 ft through interpretation. If that is how they are going to rule, that's fine as long as it's consistent and it helps everyone have fun by speeding things along.
I am glad that I found this thread and that it has been going on for over year and a half, as I am definitely going to get War Caster on my Divine Soul Sorcadin with Booming Blade, and I wanted to find out what kind of combos I can do with these... what I was surprised to see is that none of the people commenting actually mentioned some very important wordings on Opportunity Attacks and War Caster, and really disliked how Stormknight not only ignored the very first sentence for opportunity attacks, but also removed important part of the last sentence, so I will try to explain how I currently understand this situation RAW and RAI
Booming Blade
from this it's more than obvious that the creature IMMEDIATELY takes the secondary damage when it willingly moves - therefore as soon as it starts moving, and if this damage would kill it, it's corpse would stay on the square it started it's movement on
War Caster (PHB 170)
based on the first sentence; instead of taking Opportunity Attack reaction, you are essentially taking Cast a Spell reaction, which invalidates Opportunity Attack and it's behavior, and the reaction should, in fact, behave according to the Cast a Spell action, HOWEVER; according to Crawford, the spell cast has the same timing as the Opportunity Attack, thus we have to look for the timing in OA rules to determine when the Cast a Spell takes part
Opportunity Attack (PHB 195)
First sentence states that the OA triggers when a creature moves out of the reach, therefore it's crucial for the creature to actually start moving, and therefore it is not possible for the creature to decide that it wants to stay in place after OA, [just a clarification, as this has been mentioned several times]... Now, as I said before, I was surprised that no-one here mentioned the movement interruption during OA, which is, in my opinion, really crucial to this: the creature has decided to and already started to move, the movement got interrupted right before leaving your reach, at this point in time, the creature is still in your reach, but the movement has already begun, and that's when you cast your spell and hit it with Booming Blade. The creature then has to continue to move, it CAN NOT decide to stop moving mid-movement, as the interruption was not voluntary... essentially, the movement was already decided upon, and part of it already occurred, as it triggered OA, otherwise it would not trigger it, but it got interrupted right before leaving reach by the OA timing, thus the Booming Blade was casted after the creature started moving, but before leaving reach, which means the creature will continue moving when you hit it with a weapon, and therefore should immediately take the secondary damage
however what I am more interested in is what happens if the creature already has a Booming Blade effect on it... based on my own emphasis above, and how I understand RAW:
The creature has a Booming Blade effect on itself and decides to move away; because it has already started the movement [which is essential to trigger OA], the Booming Blade effect should trigger and damage the enemy [as mentioned before, Booming Blade damages the enemy immediately, and if the damage would kill the creature, it would stay on it's original square as the damage and subsequent death would interrupt the movement]. If the creature survives secondary BB damage, then it is still moving out of your reach, thus it triggers your OA, which allows you to cast Booming Blade, and it's secondary damage should trigger again because the OA timing was mid-movement, and the creature continued moving when it got hit.
Since we established the timing of OA, and there has been mentioned Sentinel feat several times I decided to give it a go as well
Again, based on when OA occurs we can clearly see that the movement started, it triggered OA, which interrupted the movement, and the sentinel then drained it's movement speed, thus the creature could not resume movement, which I understand would work similarly as if the creature would die from Booming Blade's secondary damage.
As I said, no one in this 1.5 years long thread mentioned the movement interruption, and this is how I understood RAW. I would love to hear your feedback on this, as this is how I would rule it in my games.
I also realize that the double Booming Blade proc seems rather OP, but RAW that's how I see it. However since the first sentence in OA states that you can make OA after the creature moves out of your reach, and not starts to move out of your reach, even tho the attack takes place before it leaves your reach, the wording could be interpreted as that the OA is triggered after the movement is done, but it actually [somehow, magically] takes place before the creature actually leaves your reach, just so it makes sense mechanically - so you can actually hit it [otherwise it would be too far], and to clarify where the dead body would end up. Thus RAI you could rule that the Booming Blade's secondary damage from Opportunity Attack would trigger only if the creature would move again after moving out of reach. And so to answer the original question of the thread:
RAW: 3) wreathed in booming energy 5 feet away, but already moving, so triggers extra damage immediately
RAI: 2) wreathed in booming energy 10 feet away and chooses whether or not to continue moving
Welcome to the forums.
"Not all those who wander are lost"
Of course everyone open to play this as they like, but the key wording for our game is “when a hostile creature that you can see moves out of reach”. To me this means the attack happens when the target is in the next square/hex as opposed to the threatened square/hex. (Ie the precise moment it leaves that square/hex is the moment it “moves out of reach”). The creature might then (if it realises what happening to it) choose to stop in its tracks — thus avoiding the damage from voluntarily moving.
Agree w SEnergy that it would be a pretty sweet double banger (and more at higher levels) to get a BB in place on your turn and then follow it up with another via War Caster as they move away! (At 5th lvl and higher: BANG on hit when you cast BB as an action on your turn. BANG when it moves at the start of its turn. BANG when you cast it via Warcaster as it moves out of reach. And then BANG for a fourth time if it continues its movement...
(Note - the above intentionally avoids the complication of the attack happening “right before the creature leaves your reach” as we play on a grid and maintain that creatures move in a discreet fashion from one square/hex to the next, not a continuous motion. The attempt to avoid a discussion about limits and the infinitesimally small amount of the creature remaining in the threatened square ... hmmm ... not quite as successful as I’d have liked).
Senergy,
I would contest this one point; booming blade has a range of 5ft and therefore was not RAI to wreath an opponent 10ft away.
Cheers!
Jesus Saves!... Everyone else takes damage.
I would contest your contestation, it has been consistently argued that with Polearm Master an enemy triggers the AoO at the edge of range/ square before range.
So with Polearm Master and a Spear, they enemy would be hit and stay at 10ft range, that is because starting to move starts the AoO, and then is finished before the person actually moves
that would, however, negate basic OA in the first place, as the reach of most weapons is only 5ft as well...
what I meant by RAI was that the attack actually happens while the creature is within reach, but since it's a grid and creatures do not move continuously, but rather sort of 'teleport', the movement is [and has to be] already completed when they trigger OA [first sentence of OA], and since the movement is completed already and creature is out of reach, the booming blade [which actually happened before it left reach] somehow happened after it left, but at the same time happened before it left... thus becoming wreathed in booming energy 10 feet away and chooses whether or not to continue moving... the RAI, however, sort of ignores the movement interruption, which I believe is really important
again, first and last sentences of OA say that you can make an OA after the creature leaves your reach [the movement is completed], but actually happens before it leaves your reach... thus it somehow occupies both spaces at the same time, but RAW I'd rule that the movement is not completed, but rather somehow paused, as it clearly states that it interrupts it, and creature has only begun to move
I think WotC should re-word the first sentence of OA to: You can make an opportunity attack when a hostile creature that you can see attempts to/starts to move out of your reach, which would definitely clarify that the attack happens before arriving on the next square in the grid/leaves your reach, but the current wording implies some sort of state of quantum superposition of the creature being both within and out of the reach
basically it comes down to how you interpret the movement interruption I guess... however the more I try to explain it the more I myself get confused and start to disagree with my own RAI and lean more towards RAW ruling, where the secondary booming blade effect triggers right after OA, as part of the same movement that triggered OA
I am not looking for a deep dive here, just saying booming blade does not wreath an opponent in energy, at 10ft away, under any other circumstances. e.g. a reach weapon cannot be used to deliver the spell to a target 10 ft away. So my argument is... if there is a RAW against it, then it is not reasonable to assume that wizards intended to negate that rule under a particular circumstance.
Of course, it doesn't really matter, the rule is unclear that's why this thread is still active.
As for polearm master, cheeky_hamster, those rules are written. And I dare say petty clear, but not particularly relevant to booming blade - warcaster issue being discussed here. IMO
Cheers
Jesus Saves!... Everyone else takes damage.
I am not aware of any written rules concerning the interaction of Booming Blade and Warcaster, Pole Arm Master, or even opportunity attacks. RAW is ambiguous. We are left to make inferences from RAI guidance as well as other written general and specific rules whose application (or lack of) to the situation are fair game for seven pages and a year and half worth of discussion.
"Not all those who wander are lost"
It's already in the sage advice that in order to use booming blade/ green flame blade with a 10ft reach weapon you must also have the spell sniper feat.
My understanding is that OA is interrupting the turn, not the action. OA clearly states the attack occurs as a result of the movement but retroactively takes place for the sake of melee reach mechanics.
If compared to another Wizard of the Coast product...
We would resolve the stack in reverse order.
I.E. Movement is the effect on the stack, triggers the passive ability on the board > OA, OA goes onto the stack, Replacement effect Battle Caster may be chosen
Resolve Battle Caster, resolve movement action, BB secondary effect goes on the stack, resolve secondary effect, priority returns to the active character.
This discussion really seems like an awful lot of huffing and puffing over a single d8 of damage that a DM doesn't want to let happen.
Sure there could be a situation where someone uses their own reaction to counter the spell or a reaction to redirect the attack as per various spell or class features.
Sentinal is a fairly poor comparison as it has specific wording that allows it to stop the possibility of moving retroactively in addition to the retroactive interruption that is the OA reaction.
That said, DM's word is always law.
Literal interpretations to the wind on a whim.
Afterthought..
Even if the creature is aware of the effect and has the option of stopping, it is fairly likely to not be dissuaded by that d8 of Boom unless it was potentially fatal or they found it personally quite irritating.
Any ruling is fine by me as long as: if it works for the player it works for the DM and Vice Versa.
The damage of Booming Blade does scale, so it's not always a single d8. If we that a d6 weapon was used to apply Booming Blade (purely for damage differentiation), you would have the 1d6+melee attack stat modifier + the "single d8" after voluntary movement. At fifth, that goes to 1d6 + attack mod + 1d8 on the attack + 2d8 voluntary movement trigger damage. 11th goes to 1d6 + attack mod + 2d8 + 3d8 on trigger and 17th 1d6 + attack mod + 3d8 + 4d8 on trigger. It's not groundbreaking at all, but it's stronger if the triggered damage is always present. It also stacks with hex/hunters mark, sneak attack, Great Weapon Master, and similar buffs to melee attacks and the non triggered damage is increased by crits. Not all of these stack with each other and some stack with other spell attacks, but there are some balance concerns involved that can leave party members feeling a little left behind.
The damage of Booming Blade does scale, so it's not always a single d8. If we that a d6 weapon was used to apply Booming Blade (purely for damage differentiation), you would have the 1d6+melee attack stat modifier + the "single d8" after voluntary movement. At fifth, that goes to 1d6 + attack mod + 1d8 on the attack + 2d8 voluntary movement trigger damage. 11th goes to 1d6 + attack mod + 2d8 + 3d8 on trigger and 17th 1d6 + attack mod + 3d8 + 4d8 on trigger. It's not groundbreaking at all, but it's stronger if the triggered damage is always present. It also stacks with hex/hunters mark, sneak attack, Great Weapon Master, and similar buffs to melee attacks and the non triggered damage is increased by crits. Not all of these stack with each other and some stack with other spell attacks, but there are some balance concerns involved that can leave party members feeling a little left behind.
Ah, indeed it does scale.
In term of Roleplay though I'd be inclined to compare it to walking into a trap.
You wouldn't let a player take back a move because they stepped on a trigger plate and took damage, right?
Why would you have an NPC take back the move for the very same reason?
Give the RP reason at table to justify why the spell isn't working as it mechanically should.
I don't think you need dice rolls but it might make it more palatable.
Or is the NPC so critically important to the plot that the players choosing to kill the thing they are fighting/deciding to fight is a big nono?
In what way is them downing a single NPC so game breaking?
"They did too much damage" is the same justification used to homebrew nerf Smites and Sneak attacks.
But it is still homebrew.
"But my game balance!"
Still homebrew.
There are several steps prior to the fight where the DM could have disallowed the combination.
Feats are optional Rules content.
Multi-classing is optional Rules content.
Let the Gish have the one thing they do sorta ok?
Using your trap analogy, if the trap was a pressure plate that the release of the plate caused the damage, would force the Player or the NPC to step off the plate because they stepped on in? Sure, they voluntarily stepped on the plate but some people would stop upon hearing the click (assuming that momentum didn't carry them forward, and then they'd be cringing that they didn't stop) and others would try to immediately move to clear. Depending on the nature of the trap and the knowledge of the creature, taking damage such as a nail on the plate or a dart launched at them to encourage them to move might encourage them to change their mind either way.
I'm not saying that I would do it all the time, but I don't think that it should be a case of automatic full damage.
You seem intent on misrepresenting the argument. The argument is that neither Booming Blade nor the Opportunity Attack mechanics explicitly state, nor imply, that a target of either must keep moving after being hit with either. The argument is not "that is too powerful and should be disallowed", nor "that is not overpowered, and should be allowed", nor is it "as a DM, I would really like my NPC to stay alive, so I'm not allowing it", nor "as a player, I'd like to dispatch enemies faster, so it should be allowed", nor is it "as a DM, I want to disallow that combination, so I'm claiming the rules forbid it", nor anything of the sort. Moreover, the discussion is not about game balance or individual preference, but -- as appropriate to this sub-forum -- about game mechanics, "Rules as Written". Going by that, there is no blanket prohibition on a target of Booming Blade stopping upon being hit with the spell, even if hit mid-movement. The rules allow targets to move as far as they desire, as long as they respect their speed, and to stop whenever they desire, for whatever reasons they desire. The rules do not force players to commit to a course of action once "declared" (you can even back out of a Readied Action, although you lose your Reaction by doing so). In fact, even if the rules did force character to keep moving after being hit with the spell, an Opportunity Attack, or both (via War Caster, although strictly speaking, that's not an Opportunity Attack, but rather a spell cast using your Reaction instead of an Opportunity Attack), the target would still not take the extra damage. The extra damage is triggered by willing movement. If the target does not have the option not to move, then it is not willing movement. The only argument I can see, within the rules as written, is "if the target is unaware of Booming Blade's effects, they have no logical reason for stopping their movement", which is a valid argument. Whether it's correct or not depends on the DM's interpretation of the spell's description; on whether the spell's "booming energy" that "sheathes" the target is enough to indicate, or at least suggest, that moving will cause extra damage to be taken.
Except it is right there in the OA,
"You can make an opportunity attack when a hostile creature that you can see moves out of your reach."
So, what is the creature doing? Hint, it's moving.
Sentinal has explicit wording that ceases the movement that is already in progress.
Booming Blade see's you going from tile A to tile B and says "hey, you get a boop for that", it does not stop the movement that is already in progress.
It does not ask "are you sure you wanted to walk there?"
It sees that you moved from one tile to another while under the effect and triggers.
You declared your move, that is willing movement. The fact that you didn't know the full consequences is moot.
I do find myself wondering if part of the communication issue is that I'm assuming everyone resolves movement one square at a time.
I'm not suggesting you are forced to continue moving past the one tile it took to trigger the opportunity attack.
I'm saying that the Booming Blade is applied in tile A where the Opportunity Attack is treated as hitting during the resolution of the OA, and that then it sees that you are now in tile B. Which is the tile you decided to move to voluntarily. Going from tile A to tile B being exactly the type on movement that triggers the secondary effect. Standing still or moving after that point is no longer a part of the discussion.
*Edited to be less argumentative.*
Evasion/Danger Sense etc. Are what you are thinknig about there.
Whether they keep moving or not after moving onto the square that triggered the trap is moot.
What matters is that they DID move onto the trap.
Just as they moved during the Opportunity Attack that trigger the Booming Blade.
The movement happened, it isn't up to debate.
If the was no movement there was no trigger.
You are arguing in favor of taking a move back after finding out the result in an attempt to metagame.
*Edited to be less hostile.*
I agree the person already made the choice to move which is why you got an attack of op in the first place you can't go back on that because of what war casted attack is placed on you. It happens in a split second so they wouldn't have time to react because they'd already be moving. I wish they'd actually release good sage advice on this ability because there's way to much left open for debate.