So I know this is a really old post but if the caster polymorphs themselves into an intelligence 1 or 2 creature, please explain why it doesn't interrupt concentration on spells?

— Travis Hughes (@TheRogueX) May 6, 2019

The ability to cast spells and concentrate on one has no Intelligence prerequisite in D&D, unless a rule tells you otherwise. #DnD https://t.co/wWqILsMLE5

— Jeremy Crawford (@JeremyECrawford) May 7, 2019

But aren't Polymorphed targets limited to their natural actions of their new form?
I've seen everyone just acting as their normal selves when polymorphed, even forming plans and following directions.

— Brachy [Commissions Closed] (@BrachyZoid) May 7, 2019

The ability to concentrate on a spell doesn't require you to be a member of a particular species or creature type.

The rule on concentration is a general rule that works no matter who is doing the concentrating. #DnD https://t.co/O9FXr0H55g

— Jeremy Crawford (@JeremyECrawford) May 7, 2019

@matthewmercer @mattcolville @ChrisPerkinsDnD @JeremyECrawford curious your thoughts — when one has invisibility cast upon them unknowingly, do they know they’re invisible? I imagine they could come to the conclusion shortly thru various ways, but at the initial moment? Thx

— — (@scar_dnd) March 21, 2019

If you're turned invisible without knowing it, you're in for a spooky discovery:

"Mm, that donut looks delicious …"

[reaches for donut]

"Where the hell did my hand go?!" #DnD https://t.co/Ai6Hxls51b

— Jeremy Crawford (@JeremyECrawford) March 22, 2019

Wait, so could you duel wield loaded hand crossbows?

— Zack Holloway (@ZackHolloway1) March 12, 2019

The bonus action of Crossbow Expert allows all sorts of fun combos when you combine it with the Attack action: one crossbow firing twice, two crossbows, a crossbow and a dagger, a sling and a crossbow, a pistol and a crossbow, and so on. #DnD https://t.co/3oJFOaLfWC

— Jeremy Crawford (@JeremyECrawford) March 12, 2019

@JeremyECrawford When you take the Attack action, is the trigger for the two-weapon fighting bonus action attack the entire Attack action or a single attack within the attack action? Can that particular bonus action interrupt the Attack action?

— Vaughan Cockell (@psychman27) March 11, 2019

Things like this make me beg for a restatement of Shield master, my hero. Having that bonus action between attacks instead of only after, as currently clarified, would make this Paladin exceedingly happy.

— Justin Ray Glosson (@ivstinus) March 11, 2019

As DM, I allow the bonus action of Shield Master to happen after you make at least one attack with the Attack action, since making one attack fulfills the action's basic definition (PH, 192). If you have Extra Attack, you decide which of the attacks the bonus action follows. #DnD https://t.co/L2itowmLiE

— Jeremy Crawford (@JeremyECrawford) March 11, 2019

To be clear, the clarification was that the bonus action couldn't come before you made any attacks, since you have to actually take the Attack action for the feat to work.

— Jeremy Crawford (@JeremyECrawford) March 11, 2019

As DM, I allow the BA of shield master to happen before the Attack action, as making the Attack action last during your turn is most definitely taking the Attack action during your turn. As DM, that's a legitimate way to run the feat because you know whether you're going to interrupt the character's turn and do something that might make it impossible to actually take the Attack action. The rules don't have the awareness that you have as DM.

— Jeremy Crawford (@JeremyECrawford) March 11, 2019

If you can interrupt the Attack action after one or more attacks to do a bonus action, why not allow it to be interrupted after zero attacks? The action doesn't exist if you haven't done it. The Attack action in D&D isn't an abstraction; it means an actual attack has occurred.

— Jeremy Crawford (@JeremyECrawford) March 11, 2019

Great Master @JeremyECrawford I don't understand, lot of confusion to me! RAW with Extra Attack can I use the Shield Master bonus action after the first attack or I must before complete the whole Attack action (resolve all the attacks)?

— Draconis (@DerynDraconis) March 11, 2019

The simple by-the-book way (RAW) to determine whether you've completed an action is to finish the whole action.

Yet you fulfill our design intent (RAI) with the Attack action if you make at least one attack with it, since that is how we define the action in its basic form. #DnD https://t.co/fPemHYml45

— Jeremy Crawford (@JeremyECrawford) March 11, 2019

But is that reaaaaally as much fun as running in, knocking a dude over then dropping the hammer? We're discussing what the rules say.

If a DM wants to ignore rules, go for it!

— Jeremy Crawford (@JeremyECrawford) March 11, 2019

So a monk's player can't say "I DECLARE MY ATTACK ACTION!" then make his flurry of blows attacks first, in hopes of proning w/ Open Hand, giving him advantage on his weapon attack(s)? He's got to make at least one weapon attack first, since making the attack is how you declare?

— Jason S.P. (@JandruPurdy) March 11, 2019

In D&D, the way you take an action in combat is to actually take the action. There is no action-declaration phase.

Flurry of Blows happens after the Attack action, which means the action itself, not a declaration that you will take the action. #DnD https://t.co/4TxB1M9RXo

— Jeremy Crawford (@JeremyECrawford) March 11, 2019

Of course, hindsight is 20/20. Agreed.

— Jeremy Crawford (@JeremyECrawford) March 11, 2019

I’m curious, @JeremyECrawford, what’s the reasoning for this? And I don’t mean, “because that’s how it’s written”, I mean why is it written in this way? I’m going to be honest, I house rules this on my first pass of the rules and my game has never suffered for it. #DnDTo clarify, I'm specifically talking about bonus actions having to follow actions when the two are tied together. If I, the DM, hold the character to the action if they make the BA, then what benefit is there to a rule that says the BA must follow the action? #DnD

— Dungeon Master's Workshop (@DMsWorkshop) March 11, 2019

In D&D combat, many things can prevent your intentions from manifesting. Your foes can take reactions that incapacitate you or otherwise derail a plan. Or a trap might suddenly make your intended action impossible.

What you do is what matters, not what you intend to do. #DnD https://t.co/ELizQ6VM5H

— Jeremy Crawford (@JeremyECrawford) March 11, 2019

Even if the player commits to taking the action, they might be incapacitated by a trap or another creature’s reaction before they get around to doing it. I fail to see how this can meaningfully impact the game. Take a crossbow expert who attacks with a crossbow (BA) before running in with their sword for the Attack action. That seems far more reasonable of a tactic to learn than running in AND THEN shooting. (1/2)

— Dungeon Master's Workshop (@DMsWorkshop) March 12, 2019

The bonus action of Crossbow Expert is set up by an attack with a one-handed weapon (PH, p. 165).

Notice I didn't write "a melee attack" or "a melee weapon."

There are multiple one-handed weapons in D&D that can make ranged attacks. #DnD https://t.co/MhA9kqsLWO

— Jeremy Crawford (@JeremyECrawford) March 12, 2019