Note that releasing the readied spell is not casting it (that was already done as an action), so it can't be countered at this time. Something to consider: Ready a spell behind cover and come out and blasting.
In my opinion this idea doesn't quite work as intended according to the RAW.
While it is true that an adversary would be unable to counterspell your spellcasting if he cannot see you, it also follows that you would be unable to target that adversary with your spell since you cannot see him (or, more precisely, since you do not have a clear path to the target). The target for a spell is chosen when the spell is cast, not when the spell's energy is released. (See Below) When you Ready the spell, it is fully cast at that moment that you are taking your action, not later on when you are taking your reaction.
You could still take some advantage of this concept with AOE spells though. If you position yourself behind cover so that you cannot quite see the adversary, but you can see the ground right next to him then you could land something like a Fireball spell in that spot that you can see and the ensuing blast would damage the foe. This has nothing to do with trying to use the Ready action to move your position on the battlefield however.
From Chapter 10: Spellcasting, we have rules and procedures for casting a spell under the major heading "Casting a Spell", which states:
When a character casts any spell, the same basic rules are followed . . .
Each spell description begins with a block of information, including the spell's name, level, school of magic, casting time, range, components, and duration. The rest of a spell entry describes the spell's effect.
Within this section describing "Casting a Spell", there is a subsection called "Targets" which explain the various rules for targeting when casting a spell. This subsection explains the following:
A typical spell requires you to pick one or more targets to be affected by the spell's magic. A spell's description tells you whether the spell targets creatures, objects, or a point of origin for an area of effect.
and
A Clear Path to the Target
To target something, you must have a clear path to it, so it can't be behind total cover.
So, in summary, there are 4 scenarios: [...]
The target is chosen when the spell is released, or in other words, when the reaction is taken.
In reality, the Player's Handbook doesn't state that you have to choose a target at the moment you start to cast a spell. Let me quote your own text from the book, which says two things:
"A typical spell requires you to pick one or more targets to be affected by the spell's magic", but it doesn't specify when. However, it should definitely be after the casting is completed, ant that include when you take the readied action.
"To target something, you must have a clear path to it, so it can't be behind total cover.", therefore, when you target something when the spell is released (in this case, when the trigger occurs), you must have a clear path to it.
From the Player's Handbook, p. 192:
When you ready a spell, you cast it as normal but hold its energy, which you release with your reaction when the trigger occurs. [...] For example, if you are concentrating on the web spell and ready magic missile, your web spell ends, and if you take damage before you release magic missile with your reaction, your concentration might be broken.
It's true you also need a clear path to the target when you release the energy, but if the spell requires a creature to target, that creature will be there when the trigger occurs.
For me, readying a spell is similar to readying a melee or range attack, where you can plan the attack when the target isn't yet targetable, even when the rules about Making an Attack (Player's Handbook, p. 193) requires to choose a target as the first step.
I respectfully disagree with the Sage Advice on this topic which seems to lump spellcasting together with other types of actions when taking the Ready action. These very explicitly do not work the same way. I also disagree with the above comments which support the Sage Advice ruling:
The target is chosen when the spell is released, or in other words, when the reaction is taken.
No, this is something that is required during the process of casting the spell. The section on "Targets" is a subsection within the main section of text which describes "Casting a Spell". Just like how the target must be within range when the spell is cast and how there must be a valid target to cast the spell and how you must have an appropriate spell slot available when casting the spell and how you need to have the necessary free hand and/or access to the appropriate spell components when casting the spell and so on and so forth -- targeting is also done when casting the spell.
In reality, the Player's Handbook doesn't state that you have to choose a target at the moment you start to cast a spell.
It does though. Well, not necessarily at the moment you start to cast the spell -- nobody has made that claim. But definitely during the spellcasting process. The entire "Targets" subsection exists within the "Casting a Spell" section which describes the things that are involved when casting a spell. It explains that "When a character casts any spell, the same basic rules are followed . . ." Those basic rules are detailed in the various subsections which describe concepts such as Casting Time, Range, Components, Duration, Targets and Areas Of Effect -- these things are all resolved when the spell is cast.
"A typical spell requires you to pick one or more targets to be affected by the spell's magic", but it doesn't specify when. However, it should definitely be after the casting is completed . . .
No, you don't select your targets for a spell after you've already cast it -- that doesn't make any sense and that is not what the rules say. Many spell effects occur instantaneously so it would be literally impossible to choose targets after the spell has already been cast. Again, the rules DO specify when targeting occurs: "When a character casts any spell, the same basic rules are followed . . ."
It's true you also need a clear path to the target when you release the energy, but if the spell requires a creature to target, that creature will be there when the trigger occurs.
This is definitely not necessarily true at all. All sorts of things could happen between the moment that you Ready a Spell and the moment you release it. The creature may have vaporized. The creature might have teleported. The creature might have been slain. The creature might have ducked down behind cover and ran away through an underground tunnel. And so on.
For me, readying a spell is similar to readying a melee or range attack, where you can plan the attack when the target isn't yet targetable, even when the rules about Making an Attack (Player's Handbook, p. 193) requires to choose a target as the first step.
Well, this is the important bit of this discussion. While this notion is somewhat well aligned with the Sage Advice, it couldn't be more incorrect. These are totally different situations, they are explicitly differentiated within the Ready an Action description and the supporting rules work completely differently in the mechanical sense.
The rules for Making an Attack occur within its own section of Chapter 9: Combat. These describe the rules and procedures to follow at the moment that the character actually makes an attack. Not to be confused with taking the Attack Action, or Readying an Attack or any other action that RESULTS IN actually making an attack. Once you are actually making an attack, the first step is to choose a target. However, when you take the Ready Action to Ready an attack, you haven't actually made the attack yet. This is an extremely important distinction here.
According to the rules for the Ready Action: "First, you decide what perceivable circumstance will trigger your reaction. Then, you choose the action you will take in response to that trigger . . ."
However, when you take the Ready Action to Ready a spell, the rules VERY explicitly state that it works differently for spells:
When you ready a spell, you cast it as normal but hold its energy, which you release with your reaction when the trigger occurs. To be readied, a spell must have a casting time of 1 action, and holding onto the spell's magic requires concentration. If your concentration is broken, the spell dissipates without taking effect.
So, in this case, instead of choosing the action you WILL take in response to the trigger, you've ALREADY taken the action! You've already cast the spell. It is explicitly different. This is why the spell dissipates without taking effect if your concentration is broken or if the trigger never occurs -- because you've already cast the spell.
It's true you also need a clear path to the target when you release the energy, but if the spell requires a creature to target, that creature will be there when the trigger occurs.
This is definitely not necessarily true at all. All sorts of things could happen between the moment that you Ready a Spell and the moment you release it. The creature may have vaporized. The creature might have teleported. The creature might have been slain. The creature might have ducked down behind cover and ran away through an underground tunnel. And so on.
In that sentence, I meant that when you release the energy and the spell requires a creature and a clear path to it, both requirements must be present when the trigger occurs.
For example, “If a goblin enters in the room, I will launch an Eldritch Blast at him”. When the trigger occurs, you will have that creature there because it happened; otherwise, you lose your spell.
The rules for Making an Attack occur within its own section of Chapter 9: Combat. These describe the rules and procedures to follow at the moment that the character actually makes an attack. Not to be confused with taking the Attack Action, or Readying an Attack or any other action that RESULTS IN actually making an attack. Once you are actually making an attack, the first step is to choose a target. However, when you take the Ready Action to Ready an attack, you haven't actually made the attack yet. This is an extremely important distinction here.
According to the rules for the Ready Action: "First, you decide what perceivable circumstance will trigger your reaction. Then, you choose the action you will take in response to that trigger . . ."
Yes, spells have their own chapter and rules, but as I said, for me, this is very similar to when you Ready an Action:
When you take the Ready Action to ready an attack, you haven't actually made the attack yet.
When you take the Ready Action to ready a spell, you haven't actually released the spell yet.
I know I cannot convince you, but no problem, mate. Everyone has their own way!
If a spellcaster is affected by slow and takes two turns to finish casting a spell, what happens if their target has moved out of range or out of sight?
You choose the targets of a spell when you complete casting a spell, not when you start. (slow)
And it's true; otherwise, you wouldn't be able to cast some spells with longer casting times (including rituals) that require a creature and a clear path to it. At the end of the specified casting time, the spell is released, and the different conditions and requirements must be met.
I have a problem with any rulings (even -- probably especially -- when it comes from the SAC) that is just an assertion without rules support. I'm not going to choose a side on this because it seems like the rules really don't say, but if the rules really expect you to select the target when you finish casting a spell, then that really needs to be stated somewhere in the rules. (Likewise, if the rules really expected you to choose when you started, then that should be stated directly too.)
This problem also highlights another issue with the writing of the 2014 ruleset: often general rules were written with only a single case in mind. It really seems like most of the spellcasting chapter was written only considering 1 action spells, and most of the rest of the rules in the chapter assume you are casting 1 action spells. A readied spell is no longer a 1 action cast.
For example, “If a goblin enters in the room, I will launch an Eldritch Blast at him”. When the trigger occurs, you will have that creature there because it happened; otherwise, you lose your spell.
I agree with tarodnet. If you had to choose the target when you readied the spell, you would never be able to ready a spell to blast someone about to come through a door.
I recognize that tons of people play this way. I'm just not convinced that this is technically allowed by the rules.
The same thing would apply for readying a weapon attack. If you have a sword but have run out of movement, you can ready an action to attack the first enemy that comes within range. You're not choosing a target, but readying an attack.
I just want to push back against this argument one more time. The rules explicitly differentiate between these two situations. Readying a weapon attack without seeing the target IS allowed by the rules. As per the rules for the Ready action you are preparing to take an action that you haven't actually done yet. Once you actually get to a moment of time where we are following the procedures outlined in the Making an Attack section of the rules, the target for the weapon is THEN chosen at that time.
Readying a spell is explicitly handled differently. There is an entire additional paragraph dedicated to handling this case within the rules for the Ready action whereby it is clear that the spell has already been cast. If these cases were handled in a similar way then in the case of a weapon attack you would have already fired your bow, for example, but you would be somehow freezing the bowstring in mid-air until some later moment. In that case, if there was no legal target at the time then you would not be able to Ready the attack. But again, the rules for the Ready action explicitly handle these two cases differently.
Anyway, I do agree with WolfOfTheBees that these rules could have been more clear. I'm not going to die on this hill, I am just pointing out what the rules are saying. If you are interpreting what the rules say differently then that's fine. In terms of the rule of cool it's probably more fun to play it the way that you all are saying anyway.
I can see both sides of this discussion, but in my opinion, targeting is decided when the spell is released/fully cast and not at the beginning of casting the spell. However, that is not explicitly written in the rule book so if a DM wants to enforce targeting of a spell at the beginning of casting (and the related effect of requiring this when readying a spell) then that is fine. However, keep in mind that neither or both of these rulings are RAW since the rules don't state at what point in casting a spell, the target and other constraints must be imposed.
Ready Spell: "When you ready a spell, you cast it as normal but hold its energy, which you release with your reaction when the trigger occurs. To be readied, a spell must have a casting time of 1 action, and holding onto the spell’s magic requires concentration (explained in chapter 10). If your concentration is broken, the spell dissipates without taking effect. For example, if you are concentrating on the web spell and ready magic missile, your web spell ends, and if you take damage before you release magic missile with your reaction, your concentration might be broken."
The spell is cast as normal but its energy is held and the spell released when the trigger occurs. A DM could decide that "cast as normal" means that all parameters of the spell including targeting are required as the spell is cast. However, there is no definition in the rules about what "hold its energy" means. There is also no defintion of what it means to "release" the spell. Presumably "releasing" is the same as completing the spell if you cast it within your turn as an action. RAW does not address spell casting with that level of granularity.
"Targets
A typical spell requires you to pick one or more targets to be affected by the spell’s magic."
The targeting rules only require that a target needs to be selected. It does not state whether this occurs when the spell is initially cast or when the spell is completed or released. This is then a DM call as to how they want to run it.
Finally, as mentioned, there are relevant statements in the Sage Advice Compendium. Keep in mind that the SAC is NOT a random tweet in a Sage Advice column. There are many Sage Advice comments that have never made it into the SAC. According to the SAC "Official rulings on how to interpret rules are made here in the Sage Advice Compendium." .. these are official rulings and thus also reflect the design intent of the game. Someone actually thought about the SAC entries, unlike a lot of the Sage Advice column posts. However, as always "A Dungeon Master adjudicates the game and determines whether to use an official ruling in play. The DM always has the final say on rules questions."
So, DMs can ignore the SAC if they prefer, however, since these are official rulings they also reflect something of what the designer intended.
In this case,
"For readying a spell or other action, does the target have to be in range?
Your target must be within range when you take a readied action, not when you first ready it."
The INTENT is for the range to be checked when the readied spell is released NOT when you first ready it.
"Can you ready dispel magic to stop another spell from taking effect?
The easiest way to stop a spell is to cast counterspell on its caster while it’s being cast. If successful, counterspell interrupts the other spell’s casting, and that spell fails to take effect. Counterspell works against any spell, regardless of a spell’s casting time or duration.
With the Ready action, dispel magic can be cast in response to another spell being cast, yet dispel magic can’t substitute for counterspell. The main reason is that dispel magic removes a spell that is already on a target, whether that target is a creature, an object, or some other phenomenon. Dispel magic can’t dispel something in advance. If a spell isn’t already present on a target, dispel magic does nothing to that target. The best that a readied dispel magic can do is dispel a spell immediately after the spell has been cast to prevent it from having any effect after the action used to cast it. For example, on your turn you could say something like this: “I ready dispel magic, and if the high priest casts a spell on anyone, I cast dispel magic on the target if the spell takes hold.” If the high priest then cast hold person on your companion who fails the save against it, you could unleash your readied dispel magic and end hold person."
The INTENT is for the target of the spell to be present when the spell is released NOT when it is first readied. Dispel Magic in this example is cast against a magical effect that doesn't even exist when the spell itself is readied. Requiring targeting when the spell is initially cast would prevent this from working.
"If a spellcaster is affected by slow and takes two turns to finish casting a spell, what happens if their target has moved out of range or out of sight?
You choose the targets of a spell when you complete casting a spell, not when you start. (slow)"
The INTENT is that the targets of a spell are selected when you complete the casting (the spell is released) and NOT when it is initially cast.
------------------
The bottom line here is that RAW does NOT define whether targeting is done at the beginning of casting a spell or when the spell is released. However, the official rulings in the SAC make it extremely clear that the INTENT is that targeting and range considerations are resolved when the spell is released and not when it is initially cast either in the cast of multi-round spells due to the effect of Slow or due to the use of a spell as a readied action.
A DM is welcome to rule otherwise since RAW doesn't stipulate either way but RAI appears to be made very clear with several SAC rulings.
To me RAW support SAC official ruling. When you ready a spell, you cast it as normal but hold its energy, which you release with your reaction when the trigger occurs. The rest of a spell entry describes the spell's effect. which is usually where the target is identified. In other words, target's choice is part of spell's effect when it materialize. For example;
When you ready web, only when you release it as a reaction that "You conjure a mass of thick, sticky webbing at a point of your choice within range. The webs fill a 20-foot cube from that point for the duration."
When you ready magic missile, only when you release it as a reaction that "You create three glowing darts of magical force. Each dart hits a creature of your choice that you can see within range."
When you ready bless, only when you release it as a reaction that "You bless up to three creatures of your choice within range."
Casting a Spell: When a character casts any spell, the same basic rules are followed, regardless of the character's class or the spell's effects. Each spell description begins with a block of information, including the spell's name, level, school of magic, casting time, range, components, and duration. The rest of a spell entry describes the spell's effect.
Ok, that's a good argument regarding the targeting and range considerations often being part of the spell effect rather than the spell parameters since these often only appear within the description. So the spell is fully cast but the spell effect has not yet occurred. I could buy that. This seems like a reasonable interpretation.
Yeah, logically I don't like it at all. It doesn't make sense to me that you can cast a spell without choosing the targets or when there are no valid targets. But I have to admit that the text does support that as one of the possible valid interpretations. Carry on!
Again, I think this isn’t something the rules directly state.
Although, the rules do imply that the reaction condition for the readied action can be stated with an ambiguous target implied in it: “If the goblin steps next to me, I move away.”
The rules don't need to state it directly, they don't say you must choose target as part of the rigger for your reaction when taking the Ready action, just in exemples, so you choose target when you execute your reaction and attack or release the spell's effect as well as where you move as you go, since this is the way it's normally done and nothing in Ready An Action specifically changes that.
RAW you dont choose target when casting the spell, but when the spell's effect goes, this wether you Ready a spell, cast one with Longer Casting Time or when delayed by a slow spell.
They're not so different in fact, wether you ready an attack or a spell, you hold it until you release it as a reaction on target(s) of your choosing.
But that's the thing, you don't ready "an attack", you ready the "attack action". And picking a target is something you do when making an individual attack, not when you decide to take the attack action. So I agree with @up2ng that there is a big difference in how it works when readying a weapon attack and a spell. That said I would absolutely allow the targeting to be made when the spell is released.
Here's the official ruling in Sage Advice Compendium on this topic;
The target is chosen when the spell is released, or in other words, when the reaction is taken.
In reality, the Player's Handbook doesn't state that you have to choose a target at the moment you start to cast a spell. Let me quote your own text from the book, which says two things:
From the Player's Handbook, p. 192:
It's true you also need a clear path to the target when you release the energy, but if the spell requires a creature to target, that creature will be there when the trigger occurs.
For me, readying a spell is similar to readying a melee or range attack, where you can plan the attack when the target isn't yet targetable, even when the rules about Making an Attack (Player's Handbook, p. 193) requires to choose a target as the first step.
I respectfully disagree with the Sage Advice on this topic which seems to lump spellcasting together with other types of actions when taking the Ready action. These very explicitly do not work the same way. I also disagree with the above comments which support the Sage Advice ruling:
No, this is something that is required during the process of casting the spell. The section on "Targets" is a subsection within the main section of text which describes "Casting a Spell". Just like how the target must be within range when the spell is cast and how there must be a valid target to cast the spell and how you must have an appropriate spell slot available when casting the spell and how you need to have the necessary free hand and/or access to the appropriate spell components when casting the spell and so on and so forth -- targeting is also done when casting the spell.
It does though. Well, not necessarily at the moment you start to cast the spell -- nobody has made that claim. But definitely during the spellcasting process. The entire "Targets" subsection exists within the "Casting a Spell" section which describes the things that are involved when casting a spell. It explains that "When a character casts any spell, the same basic rules are followed . . ." Those basic rules are detailed in the various subsections which describe concepts such as Casting Time, Range, Components, Duration, Targets and Areas Of Effect -- these things are all resolved when the spell is cast.
No, you don't select your targets for a spell after you've already cast it -- that doesn't make any sense and that is not what the rules say. Many spell effects occur instantaneously so it would be literally impossible to choose targets after the spell has already been cast. Again, the rules DO specify when targeting occurs: "When a character casts any spell, the same basic rules are followed . . ."
This is definitely not necessarily true at all. All sorts of things could happen between the moment that you Ready a Spell and the moment you release it. The creature may have vaporized. The creature might have teleported. The creature might have been slain. The creature might have ducked down behind cover and ran away through an underground tunnel. And so on.
Well, this is the important bit of this discussion. While this notion is somewhat well aligned with the Sage Advice, it couldn't be more incorrect. These are totally different situations, they are explicitly differentiated within the Ready an Action description and the supporting rules work completely differently in the mechanical sense.
The rules for Making an Attack occur within its own section of Chapter 9: Combat. These describe the rules and procedures to follow at the moment that the character actually makes an attack. Not to be confused with taking the Attack Action, or Readying an Attack or any other action that RESULTS IN actually making an attack. Once you are actually making an attack, the first step is to choose a target. However, when you take the Ready Action to Ready an attack, you haven't actually made the attack yet. This is an extremely important distinction here.
According to the rules for the Ready Action: "First, you decide what perceivable circumstance will trigger your reaction. Then, you choose the action you will take in response to that trigger . . ."
However, when you take the Ready Action to Ready a spell, the rules VERY explicitly state that it works differently for spells:
So, in this case, instead of choosing the action you WILL take in response to the trigger, you've ALREADY taken the action! You've already cast the spell. It is explicitly different. This is why the spell dissipates without taking effect if your concentration is broken or if the trigger never occurs -- because you've already cast the spell.
In that sentence, I meant that when you release the energy and the spell requires a creature and a clear path to it, both requirements must be present when the trigger occurs.
For example, “If a goblin enters in the room, I will launch an Eldritch Blast at him”. When the trigger occurs, you will have that creature there because it happened; otherwise, you lose your spell.
Yes, spells have their own chapter and rules, but as I said, for me, this is very similar to when you Ready an Action:
I know I cannot convince you, but no problem, mate. Everyone has their own way!
Only one more thing. We have also this official ruling in the Sage Advice Compendium:
And it's true; otherwise, you wouldn't be able to cast some spells with longer casting times (including rituals) that require a creature and a clear path to it. At the end of the specified casting time, the spell is released, and the different conditions and requirements must be met.
I have a problem with any rulings (even -- probably especially -- when it comes from the SAC) that is just an assertion without rules support. I'm not going to choose a side on this because it seems like the rules really don't say, but if the rules really expect you to select the target when you finish casting a spell, then that really needs to be stated somewhere in the rules. (Likewise, if the rules really expected you to choose when you started, then that should be stated directly too.)
This problem also highlights another issue with the writing of the 2014 ruleset: often general rules were written with only a single case in mind. It really seems like most of the spellcasting chapter was written only considering 1 action spells, and most of the rest of the rules in the chapter assume you are casting 1 action spells. A readied spell is no longer a 1 action cast.
I recognize that tons of people play this way. I'm just not convinced that this is technically allowed by the rules.
I just want to push back against this argument one more time. The rules explicitly differentiate between these two situations. Readying a weapon attack without seeing the target IS allowed by the rules. As per the rules for the Ready action you are preparing to take an action that you haven't actually done yet. Once you actually get to a moment of time where we are following the procedures outlined in the Making an Attack section of the rules, the target for the weapon is THEN chosen at that time.
Readying a spell is explicitly handled differently. There is an entire additional paragraph dedicated to handling this case within the rules for the Ready action whereby it is clear that the spell has already been cast. If these cases were handled in a similar way then in the case of a weapon attack you would have already fired your bow, for example, but you would be somehow freezing the bowstring in mid-air until some later moment. In that case, if there was no legal target at the time then you would not be able to Ready the attack. But again, the rules for the Ready action explicitly handle these two cases differently.
Anyway, I do agree with WolfOfTheBees that these rules could have been more clear. I'm not going to die on this hill, I am just pointing out what the rules are saying. If you are interpreting what the rules say differently then that's fine. In terms of the rule of cool it's probably more fun to play it the way that you all are saying anyway.
I can see both sides of this discussion, but in my opinion, targeting is decided when the spell is released/fully cast and not at the beginning of casting the spell. However, that is not explicitly written in the rule book so if a DM wants to enforce targeting of a spell at the beginning of casting (and the related effect of requiring this when readying a spell) then that is fine. However, keep in mind that neither or both of these rulings are RAW since the rules don't state at what point in casting a spell, the target and other constraints must be imposed.
Ready Spell: "When you ready a spell, you cast it as normal but hold its energy, which you release with your reaction when the trigger occurs. To be readied, a spell must have a casting time of 1 action, and holding onto the spell’s magic requires concentration (explained in chapter 10). If your concentration is broken, the spell dissipates without taking effect. For example, if you are concentrating on the web spell and ready magic missile, your web spell ends, and if you take damage before you release magic missile with your reaction, your concentration might be broken."
The spell is cast as normal but its energy is held and the spell released when the trigger occurs. A DM could decide that "cast as normal" means that all parameters of the spell including targeting are required as the spell is cast. However, there is no definition in the rules about what "hold its energy" means. There is also no defintion of what it means to "release" the spell. Presumably "releasing" is the same as completing the spell if you cast it within your turn as an action. RAW does not address spell casting with that level of granularity.
"Targets
A typical spell requires you to pick one or more targets to be affected by the spell’s magic."
The targeting rules only require that a target needs to be selected. It does not state whether this occurs when the spell is initially cast or when the spell is completed or released. This is then a DM call as to how they want to run it.
Finally, as mentioned, there are relevant statements in the Sage Advice Compendium. Keep in mind that the SAC is NOT a random tweet in a Sage Advice column. There are many Sage Advice comments that have never made it into the SAC. According to the SAC "Official rulings on how to interpret rules are made here in the Sage Advice Compendium." .. these are official rulings and thus also reflect the design intent of the game. Someone actually thought about the SAC entries, unlike a lot of the Sage Advice column posts. However, as always "A Dungeon Master adjudicates the game and determines whether to use an official ruling in play. The DM always has the final say on rules questions."
So, DMs can ignore the SAC if they prefer, however, since these are official rulings they also reflect something of what the designer intended.
In this case,
"For readying a spell or other action, does the target have to be in range?
Your target must be within range when you take a readied action, not when you first ready it."
The INTENT is for the range to be checked when the readied spell is released NOT when you first ready it.
"Can you ready dispel magic to stop another spell from taking effect?
The easiest way to stop a spell is to cast counterspell on its caster while it’s being cast. If successful, counterspell interrupts the other spell’s casting, and that spell fails to take effect. Counterspell works against any spell, regardless of a spell’s casting time or duration.
With the Ready action, dispel magic can be cast in response to another spell being cast, yet dispel magic can’t substitute for counterspell. The main reason is that dispel magic removes a spell that is already on a target, whether that target is a creature, an object, or some other phenomenon. Dispel magic can’t dispel something in advance. If a spell isn’t already present on a target, dispel magic does nothing to that target. The best that a readied dispel magic can do is dispel a spell immediately after the spell has been cast to prevent it from having any effect after the action used to cast it. For example, on your turn you could say something like this: “I ready dispel magic, and if the high priest casts a spell on anyone, I cast dispel magic on the target if the spell takes hold.” If the high priest then cast hold person on your companion who fails the save against it, you could unleash your readied dispel magic and end hold person."
The INTENT is for the target of the spell to be present when the spell is released NOT when it is first readied. Dispel Magic in this example is cast against a magical effect that doesn't even exist when the spell itself is readied. Requiring targeting when the spell is initially cast would prevent this from working.
"If a spellcaster is affected by slow and takes two turns to finish casting a spell, what happens if their target has moved out of range or out of sight?
You choose the targets of a spell when you complete casting a spell, not when you start. (slow)"
The INTENT is that the targets of a spell are selected when you complete the casting (the spell is released) and NOT when it is initially cast.
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The bottom line here is that RAW does NOT define whether targeting is done at the beginning of casting a spell or when the spell is released. However, the official rulings in the SAC make it extremely clear that the INTENT is that targeting and range considerations are resolved when the spell is released and not when it is initially cast either in the cast of multi-round spells due to the effect of Slow or due to the use of a spell as a readied action.
A DM is welcome to rule otherwise since RAW doesn't stipulate either way but RAI appears to be made very clear with several SAC rulings.
To me RAW support SAC official ruling. When you ready a spell, you cast it as normal but hold its energy, which you release with your reaction when the trigger occurs. The rest of a spell entry describes the spell's effect. which is usually where the target is identified. In other words, target's choice is part of spell's effect when it materialize. For example;
When you ready web, only when you release it as a reaction that "You conjure a mass of thick, sticky webbing at a point of your choice within range. The webs fill a 20-foot cube from that point for the duration."
When you ready magic missile, only when you release it as a reaction that "You create three glowing darts of magical force. Each dart hits a creature of your choice that you can see within range."
When you ready bless, only when you release it as a reaction that "You bless up to three creatures of your choice within range."
Ok, that's a good argument regarding the targeting and range considerations often being part of the spell effect rather than the spell parameters since these often only appear within the description. So the spell is fully cast but the spell effect has not yet occurred. I could buy that. This seems like a reasonable interpretation.
Good point about the intent in "Can you ready dispel magic to stop another spell from taking effect?", David42.
And well, I'm happy if Plaguescarred's point of view convinced you, up2ng.
Who knows... maybe these kind of things are described in more detail in the 20204 PHB or DMG.
Yeah, logically I don't like it at all. It doesn't make sense to me that you can cast a spell without choosing the targets or when there are no valid targets. But I have to admit that the text does support that as one of the possible valid interpretations. Carry on!
I can see it both ways. It comes down to, for me, how you interpret the part that says you cast the spell as normal.
So if you are in a completely empty room and want to cast a spell like Magic Missile or Eldritch Blast as an action (not readied) can you do so?
EZD6 by DM Scotty
https://www.drivethrurpg.com/en/product/397599/EZD6-Core-Rulebook?
It also align with when you ready an attack but only choose target when attacking as a reaction.
Readying an attack is explicitly different than readying a spell. See above posts.
They're not so different in fact, wether you ready an attack or a spell, you hold it until you release it as a reaction on target(s) of your choosing.
Again, I think this isn’t something the rules directly state.
Although, the rules do imply that the reaction condition for the readied action can be stated with an ambiguous target implied in it: “If the goblin steps next to me, I move away.”
The rules don't need to state it directly, they don't say you must choose target as part of the rigger for your reaction when taking the Ready action, just in exemples, so you choose target when you execute your reaction and attack or release the spell's effect as well as where you move as you go, since this is the way it's normally done and nothing in Ready An Action specifically changes that.
RAW you dont choose target when casting the spell, but when the spell's effect goes, this wether you Ready a spell, cast one with Longer Casting Time or when delayed by a slow spell.
But that's the thing, you don't ready "an attack", you ready the "attack action". And picking a target is something you do when making an individual attack, not when you decide to take the attack action. So I agree with @up2ng that there is a big difference in how it works when readying a weapon attack and a spell. That said I would absolutely allow the targeting to be made when the spell is released.
There is a difference between them., but not so much in the perspective of choosing target for it, which was the debate in question.