D&D 5E Can you twin booming blade

[Salthorae]

That is simply not what the text of the spell says.

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,

The spell forces you to make a melee weapon attack or it fails. They're not separate distinct actions.

 

[Charlaquin]

The spell forces you to make a melee weapon attack or it fails. They're not separate distinct actions.

The spell requires you to make an attack with a melee weapon against one creature within the spell’s range (it doesn’t even say “against the target!”) as part of the action used to cast it or the spell fails. It does not cause you to make an attack as part of the effect of the successfully cast spell, like Ray of Frost does.

 

[Krachek]

I’m still very happy that those cantrip booming and green flame didn’t make Xanathar guide.

 

[Charlaquin]

I’m still very happy that those cantrip booming and green flame didn’t make Xanathar guide.

I agree, they’re so kludgy.

 

[Ashrym]

The spell requires you to make an attack with a melee weapon as part of the action used to cast it or the spell fails. It does not cause you to make an attack as part of the effect of the successfully cast spell, like Ray of Frost does.

Crawford has stated the opposite at least twice that I know of.

There's nothing stopping the sorcerer from making multiple attacks because there was never a separate action required to make an attack as part of casting the spell. The attack is part of the cast a spell action with no separate requirement or action of any sort. Twin just changes it to two targets that still don't need any separate requirements to make those melee attacks.

The only way for "must make a melee attack with a weapon" to be restricted is if there's an action cost stated in the spell. There isn't, and if we assume a melee action is required the spell becomes impossible because the sorcerer would have needed two actions in the first place.

The melee attack is part of the spell. Twinning booming blade does to two targets what not twinning it does to one target. That's no different than any other twinned spell.

 

[LordEntrails]

So... you can twin a booming blade?

As for hasting or action surging, I would say no. Not for any reasons given, but because you can only cast 1 spell per round unless the second is a cantrip cast as a bonus action (which only quickened spell does right?) (Or if valid as a reaction).

Did I miss something?

 

[Salthorae]

As for hasting or action surging, I would say no. Not for any reasons given, but because you can only cast 1 spell per round unless the second is a cantrip cast as a bonus action (which only quickened spell does right?) (Or if valid as a reaction).

You absolutely can cast more than 1 spell per round using action surge. Not with haste though. If you were to quicken/bonus action cast a spell, you could cast a cantrip, and with action surge you could cast another cantrip. So a SorLock could cast 3 Eldritch Blasts in a round.

You could cast two twin spells in a round with Action Surge, and a reaction as valid.

So... you can twin a booming blade?

Haha, yup

 

[Ashrym]

So... you can twin a booming blade?

As for hasting or action surging, I would say no. Not for any reasons given, but because you can only cast 1 spell per round unless the second is a cantrip cast as a bonus action (which only quickened spell does right?) (Or if valid as a reaction).

Did I miss something?

A sorcerer can twin booming blade, yes. The restriction on the spells is on a turn, not round, so action surge works, and quicken allows another booming blade on the bonus action. A sorcerer with a fighter dip for action surge can use the action surge, twin twice (2 sorc points), and quicken once (2 sorc point) to cast booming blade three times at five targets.

EDIT: technically it's among 2-5 targets. Twin needs 2 targets and repeat castings can be at the same targets.

Haste can add an attack but not with booming blade.

Sorcerers are all about the nova potential.

 

[Charlaquin]

Crawford has stated the opposite at least twice that I know of.

And I have stared at least four times that Crawford’s answers are clearly the intended function and are how I would run it at the table. I am merely arguing that the correct interpretation is not what a technical reading of the rules as written suggest.

Effectively, what I’m saying is that BB and GFB are poorly written.

There's nothing stopping the sorcerer from making multiple attacks because there was never a separate action required to make an attack as part of casting the spell. The attack is part of the cast a spell action with no separate requirement or action of any sort. Twin just changes it to two targets that still don't need any separate requirements to make those melee attacks.

I have never suggested that there is a restriction on how many attacks the sorcerer can make, nor that there is any separation between the Cast a Spell action and the attack required by Booming Blade. Quite the contrary, the very crux of my argument is that the attack is part of the action used to cast the spell, as opposed to being part of the effect of the spell.

The only way for "must make a melee attack with a weapon" to be restricted is if there's an action cost stated in the spell. There isn't, and if we assume a melee action is required the spell becomes impossible because the sorcerer would have needed two actions in the first place.

There is no such thing as a “melee action.” The Booming Blade spell instructs you to make an attack with a melee weapon against a creature within the spell’s range, or it fails. If you successfully perform this attack, and the necessary verbal and material components, then the spell targets the creature you attacked and places a condition of “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 be- fore then, it immediately takes 1d8 thunder damage, and the spell ends“ on the target. Twinning the spell lets you target a second creature with that effect. It does not, by a technical reading, cause you to make a second attack, any more than Twinning the Raise Dead causes you to expend a second 500 gp diamond.

The melee attack is part of the spell.

The melee attack is, quite explicitly, part of the action used to cast the spell, not part of the effect of the spell.

Now, we know that this was not the developer’s intent. But if the developer’s intent was for the attack to be part of the effect of the spell, it should have been worded “make a melee weapon attack” just like every other spell that causes you to make an attack as part of its effect is. The fact that it is worded “ 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,” unlike every other spell that causes you to make an attack as part of its effects, suggests an intended function that is different from every other such spell.

Twinning booming blade does to two targets what not twinning it does to one target. That's no different than any other twinned spell.

Correct. And what not twinning Booming Blade does to one target is, “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 be- fore then, it immediately takes 1d8 thunder damage, and the spell ends.”

 

[Harzel]

So... you can twin a booming blade?

As for hasting or action surging, I would say no. Not for any reasons given, but because you can only cast 1 spell per round unless the second is a cantrip cast as a bonus action (which only quickened spell does right?) (Or if valid as a reaction).

Did I miss something?

First, there is no blanket restriction on casting more than one spell per turn. The rule that you are (apparently) thinking of is that if you cast a spell as a bonus action, then any other spell that you cast must be a cantrip with a casting time of 1 action. So the restriction only comes into effect if you cast a spell as a bonus action.

Also, as someone else already noted, the restriction applies to spells cast on your turn, not during the whole round. So, for example, a spell cast as a reaction on some other creature's turn is not subject to the restriction.

As for Haste, that's really not in question because you cannot use the extra action granted by Haste to take the Cast a Spell action.