Concentration and Counterspell

[ATHATH]

Scenario:

I am concentrating on a Darkness spell that includes me in its AoE. I am within 40 ft. of an opposing Warlock (that does not have Darkvision), and try cast Web on his position. Can he cast Counterspell on it?

I have two possible theories on what might happen:
1. I cast Web, and it goes into effect. Immediately afterwards, my Darkness spell ends.
2. I begin to cast Web, and my Darkness spell ends before I finish casting Web/Web takes effect, giving the Warlock an opportunity to cast Counterspell on my Web spell.

Are either of them correct? If not, what do you think happens?

[Quintessence]

I would say number 2 occurs, your darkness fades and the other warlock can see you casting web so he is able to counterspell it.

[Erys]

I tend to feel the Darkness stays until Web is cast. Once cast, Web is now the Spell being concentrated on.

That said, since spellcasting is not secretive (as a general rule of thumb, there are exceptions), so in this case since Web has a verbal component the warlock could Counterspell it even though he is unsure where the caster is. He can hear the spell and disrupt the magic.

So my vote is 3. Web is countered, Darkness stays.

But, almost certainly, others will have different opinions so it may be best to bring it up at your table to find a local agreement on how to resolve the issue.

[Malifice]

I fall on the side of the 'darkness drops first and the Web can be counterspelled' camp.

Beats me why the caster doesnt just move 25' back first.

[NecroDancer]

I honestly don't know, it depends on if your DM thinks concertantion is broken while casting a new concentration spell or if he thinks concentration is broken once the new spell comes into effect.

[Plaguescarred]

I'd say Counterspell interrupt the process of casting Web before its fully cast and its concentration duration can take effect and end Darkness.

[NNescio]

I'd say Counterspell interrupt the process of casting Web before its fully cast and its concentration duration can take effect and end Darkness.

Unless you can see in magical darkness, you can't Counterspell the caster if Darkness doesn't drop first (before Web is cast).

[Plaguescarred]

Unless you can see in magical darkness, you can't Counterspell the caster if Darkness doesn't drop first (before Web is cast).Yeah i agree you can't really see the creature casting Web and Counterspell it yet if Darkness is still up.

[TheUser]

The act of casting doesn't break concentration; case in point you can cast lots of instantaneous spells/cantrips without breaking concentration. Once you actually finish casting the web spell the darkness breaks since you are concentrating on something else.

If you cannot see the target you intend to counter spell you cannot counter spell them.

[Mandragola]

My reading is that there's no opportunity to counterspell.

Concentration only ends when you start concentrating on something new, not when you cast any other spell. You can cast cantrips and fireballs all throughout and nobody can counterspell you if your darkness spell means they can't see you.

It's no different when you cast web. As you cast, you're in darkness. Only when you start concentrating on a new spell does your old one end.

[NNescio]

My reading is that there's no opportunity to counterspell.

Concentration only ends when you start concentrating on something new, not when you cast any other spell. You can cast cantrips and fireballs all throughout and nobody can counterspell you if your darkness spell means they can't see you.

It's no different when you cast web. As you cast, you're in darkness. Only when you start concentrating on a new spell does your old one end.

That's what I think as well (and it's how I would rule), but I believe RAW is ambiguous (because 5e is notoriously lax on the timing of events/actions) and either ruling is valid.

[Mandragola]

That's what I think as well (and it's how I would rule), but I believe RAW is ambiguous (because 5e is notoriously lax on the timing of events/actions) and either ruling is valid.

Agreed. I expect this is one of those cases where they didn't think of it, but actually it can apply in a lot of situations. For example you could be concentrating on a spell that prevents reactions by messing with the bad guy's head in some way.

[Erys]

After thinking about it, I changed my opinion some.

Even though you could hear Web being cast you probably need LoS to Counterspell it, something not afforded in Darkness. Though, arguably, even though Web is an AoE, you do need LoS for it too; so I amend my answer to #2.

[NNescio]

After thinking about it, I changed my opinion some.

Even though you could hear Web being cast you probably need LoS to Counterspell it, something not afforded in Darkness. Though, arguably, even though Web is an AoE, you do need LoS for it too; so I amend my answer to #2.

Web doesn't require LoS, only LoE (i.e. a clear path).

Of course, a DM might rule that you can't just arbitrarily center the spell on a point you haven't even seen yet. I do let my players guess though (with the point of origin shifting to the nearest surface within LoE [per the Clear Path rules] if they happen to center the PoO in a solid object), and just let them plop down PoO with exact precision if they have seen the spot within the last 10 minutes or so.

[Joe the Rat]

I opted for cast, then concentration ends. Concentrating (keeping juice flowing to a sustained effect) does not prevent spellcasting, so I'm looking at it as the effect manifesting as part of the initial casting energy, but then your mana stream/spellform maintenance/whatever switches to the new spell. Plus it's funnier that way.

Example from play: The party Warlock is Spiderclimbing across the cave ceiling, then decides to drop Hunger of Hadar on the cluster of cult fanatics that has been sacred flame/spirit weaponing the party. The instant the whispering void opened, she fell off the ceiling. Unfortunately she opted to "run like hell" (use her move for the turn) to get to a lower ceiling before casting, so she only took a 20' fall. I was so looking forward to the Wile E. Coyote moment.
She did made her concentration check.

If you do it the other way around, you'd drop in the middle of casting, potentially needing a concentration check to finish the spell.

[clash]

As others have noted Coutnerspell requires that you see the target casting:
"1 reaction, which you take when you see a creature within 60 feet of you casting a spell"

Web does not strictly require line of sight
"You conjure a mass of thick, sticky webbing at a point of your choice within range."

So the counterspeller can definitely not cast counterspell while darkness is up and the spellcaster should be able to cast web with darkness up.

As to when the darkness drops,
"You lose concentration on a spell if you cast another spell that requires concentration. You can’t concentrate on two spells at once."
Note it says when you cast and not when you start casting a spell. Again I would rule that because casting other spells that dont require concentration dont break concentration then the act of casting isnt what breaks it but rather the act of having the spell cast. Since counterspell interrupts the process of casting the spell, it triggers before the spell is cast and before the darkness drops, making unusable in this situation.

As a side effect, in cases without the darkness if a concentration spell gets counterspelled before it is cast, the caster would not lose concentration on the current spell they are concentrating on. To me this sounds like the intended effect. You shouldnt lose concentration on a spell for trying to cast a different one.

[Mandragola]

To be honest, it's not clear. The effect that triggers the darkness ending is the same thing that causes darkness to drop. Both happen when the spell is cast. Clash's quote indicates that this is the case "You lose concentration on a spell if you cast another spell that requires concentration".

There kind of isn't a two-stage process that goes: 1. cast spell, 2. concentrate on spell. Concentration on spell A ends when you cast spell B, not after that point when you start concentrating on spell B. It's the casting of concentration spell B, not concentrating on it, that ends your concentration on spell B.

So in this case a DM might well choose to rule that darkness drops during the casting of the web. In that case the web could be counterspelled, and the end result would be that no spells were in effect.

[Erys]

Web doesn't require LoS, only LoE (i.e. a clear path).

Of course, a DM might rule that you can't just arbitrarily center the spell on a point you haven't even seen yet. I do let my players guess though (with the point of origin shifting to the nearest surface within LoE [per the Clear Path rules] if they happen to center the PoO in a solid object), and just let them plop down PoO with exact precision if they have seen the spot within the last 10 minutes or so.

Hmmm, good point. Guess the effectiveness of Web depends on if the warlock was seen before Darkness was cast and whether or not he moved since then.

[Dalebert]

Good luck finding it, but there was a Sage Advice that supported that concentration ends at the start of casting a concentration spell, which would mean there's a chance to counterspell. I don't think it was Crawford. I seem to recall Perkins but I could be wrong. I seem to recall someone asking a question right along the lines of OP.

[BiPolar]

My table generally rules that concentration ends if you TRY to cast another concentration spell. You don't have to succeed, but basically once you start casting another spell that requires concentration you have to let go of the first.

In that interpretation, Once you started casting web, darkness would end and it could be counterspelled.

However, if you rule otherwise, or if another caster was casting in darkness, then it couldn't be counterspelled as the Counterspell requires Sight.