D&D 5E Dispel Magic, Ready action and Fireball

[spartanah]

When Crawford says "As a DM", it's not an official ruling. It's how he runs it at his table. And should be taken as such meaning if you want to run it that way, it's a DM call, not an official stance on a rule.

So what is RAW?
The book doesn't say, the tweet doesn't say. So who decides what is RAW? Or RAI? The guy with the most posts? Because people here say way too easy if it's RAW or RAI. But nobody can really say

 

[Hriston]

So what is RAW?
The book doesn't say, the tweet doesn't say. So who decides what is RAW? Or RAI? The guy with the most posts? Because people here say way too easy if it's RAW or RAI. But nobody can really say

As I already noted up-thread, the intent has been directly addressed by Crawford. Here's the actual tweet:

Can you Ready a Dispel Magic to trigger on an instantaneous spell's casting to interrupt the target spell's effect?
1:07 PM - 3 Jul 2015

Dispel magic isn't intended to work on instantaneous spells. Counterspell is suited for that task. https://twitter.com/JeremySoard/status/617031910460649472 …
11:03 PM - 6 Jul 2015

 

[seebs]

It's pretty clear you can't use a readied dispel as a counterspell. It's not at all obvious whether you can dispel a readied spell.

... Come to think of it, now I have a new question:

If someone readies a spell, and I have counterspell, would I use my reaction to counterspell on their turn, when they "cast" but don't release the spell, or would I use it when they use their reaction to try to release their spell?

 

[RangerWickett]

Can you ready an action to cast fog cloud to break the line of sight so an enemy cannot target you with a spell?

Can you ready an action to dodge behind a wall if someone shoots an arrow at you?

Can I house rule counterspell and dispel magic into one spell, which can be cast two different ways, depending on if you want it as a reaction or normal action?

Likewise, can I add in the 3e rule that you can ready an action to counterspell and even if you don't have counterspell or dispel magic available, as long as you have the same spell prepared/known, you can just use a slot to negate the incoming effect?

 

[seebs]

Can you ready an action to cast fog cloud to break the line of sight so an enemy cannot target you with a spell?

Can you ready an action to dodge behind a wall if someone shoots an arrow at you?

These definitely don't go, because readied actions in general happen after their triggers. You could conceivably dodge behind a wall after the first arrow is shot, and before the second.

 

[Ilbranteloth]

It's pretty clear you can't use a readied dispel as a counterspell. It's not at all obvious whether you can dispel a readied spell.

... Come to think of it, now I have a new question:

If someone readies a spell, and I have counterspell, would I use my reaction to counterspell on their turn, when they "cast" but don't release the spell, or would I use it when they use their reaction to try to release their spell?

Well, I suppose there are some circumstances where it might matter.

For example if there are multiple spell casters and you indicate that you will cast a counterspell against the first spell cast. If it's the releasing of the spell that triggers your counterspell, and the two opponents have both readied spells, one of them could take damage and fail their concentration check, in which can you counterspell the second spell. Thus both of their spells are negated in that round.

But overall I don't think it really matters, but my ruling would be when the spell is released, not readied. My reasoning would be the spell can be lost, but you don't lose a spell slot if a readied spell is disrupted. Thus there is no spell to counterspell yet.

Ilbranteloth

 

[seebs]

You do lose the spell slot if a readied spell is disrupted, though. You have used up the slot right away.