collision damage?

[Braininthejar2]

An artificer holds an action, to summon a wall of iron in the path of a charging minotaur.

What do?

[Jormengand]

The conditions of the action can no longer be made to conform, so the charge fails. The minotaur remains where it is.

[tyckspoon]

In general, voluntary movement can be voluntarily ended, so putting a barrier in its way will just mean the creature stops moving rather than smacking into the barrier. When involuntary movement (getting Bull Rushed, shoved by a spell, etc) includes rules for being stopped prematurely, it usually uses something very close to the rules for fall damage - d6 per 10 feet the character would have moved if he hadn't hit the obstruction. I would go with that as a rule of thumb if a particular spell or ability doesn't include its own specific rules for the situation.

[Jormengand]

Notably, because movement is instantaneous, and charge conditions are checked when deciding whether to move or not (and it's too late to take an immediate action between charge conditions being checked and movement occurring), it's impossible to put up a barrier at any time except for:

1) Before the charge is even declared. The minotaur doesn't lose its action and the charge doesn't take place. The minotaur can take any action that's possible given the new circumstances, including the wall.
2) After the charge has been declared, before the charge conditions are checked, and also before the charge has resolved. The minotaur's action is wasted and it does nothing because the charge conditions are checked as part of the resolution, no matter what you do to try to stop it.
3) After the charge has been resolved. The minotaur charges and you put some iron behind it. The minotaur's attack of opportunity has a chance to disrupt your spell. What exactly were you going for, here?

You cannot do it:

4) Between the check and the resolution. The check happens during the resolution, so you can't interrupt the action partway through.
5) During the resolution. Movement isn't divided up into stages you can interrupt - Zeno need not apply.

Whether you actually like that answer or not, is up to you. But be prepared for "But the rules say..." if the tables are turned and the PCs in another group want to charge your artificer.

[Necroticplague]

An artificer holds an action, to summon a wall of iron in the path of a charging minotaur.

What do?

1. Why does your title contain a question completely unrelated to the described scenario?

2. Depends on the exact wording/timing of the artificer's 'held action' (by which, I assume you mean Readied Action). Either way, the minotaur running into the wall is impossible. Either the wall is there before the charge (and the minotaur can't charge), or it's there after the charge (and the minotaur has already moved). Most likely is that the minotaur just wastes it's full-round action doing nothing, as its charge has been rendered invalid.

[DeltaEmil]

1. Why does your title contain a question completely unrelated to the described scenario? Me thinks that the OP believes that when the wall is formed while the minotaur is charging, that the minotaur would slam into the wall and take damage from colliding into it.

[Crake]

Notably, because movement is instantaneous, and charge conditions are checked when deciding whether to move or not (and it's too late to take an immediate action between charge conditions being checked and movement occurring), it's impossible to put up a barrier at any time except for:

1) Before the charge is even declared. The minotaur doesn't lose its action and the charge doesn't take place. The minotaur can take any action that's possible given the new circumstances, including the wall.
2) After the charge has been declared, before the charge conditions are checked, and also before the charge has resolved. The minotaur's action is wasted and it does nothing because the charge conditions are checked as part of the resolution, no matter what you do to try to stop it.
3) After the charge has been resolved. The minotaur charges and you put some iron behind it. The minotaur's attack of opportunity has a chance to disrupt your spell. What exactly were you going for, here?

You cannot do it:

4) Between the check and the resolution. The check happens during the resolution, so you can't interrupt the action partway through.
5) During the resolution. Movement isn't divided up into stages you can interrupt - Zeno need not apply.

Whether you actually like that answer or not, is up to you. But be prepared for "But the rules say..." if the tables are turned and the PCs in another group want to charge your artificer.

Where did you get this information that movement is instantaneous? Readied actions can interrupt movement, you can, for example, ready to shoot someone as they come around a corner, or move out into the open, interrupting their movement before they get to their destination, and if they fall unconscious at that point, they fall unconscious in the square that you shot them in, not in the square their movement would have ended at.

[Zanos]

Yeah, that would imply that you can't ready an action to attack someone who comes within your reach or moves into your sight but doesn't end movement in your sight, which I'm fairly certain are explicit examples of using readied actions in the books.

[SangoProduction]

Yeah, that would imply that you can't ready an action to attack someone who comes within your reach or moves into your sight but doesn't end movement in your sight, which I'm fairly certain are explicit examples of using readied actions in the books.

Stand Still feat does interrupt the movement though, as would hold person.

[DeTess]

As several people have pointed out, this doesn't work out in RAW. However, if I was a DM in this game, I'd probably rule it as doing damage as if the creature had fallen a distance equal to half it's movement speed.

[KillianHawkeye]

Notably, because movement is instantaneous, and charge conditions are checked when deciding whether to move or not (and it's too late to take an immediate action between charge conditions being checked and movement occurring), it's impossible to put up a barrier at any time except for:

1) Before the charge is even declared. The minotaur doesn't lose its action and the charge doesn't take place. The minotaur can take any action that's possible given the new circumstances, including the wall.
2) After the charge has been declared, before the charge conditions are checked, and also before the charge has resolved. The minotaur's action is wasted and it does nothing because the charge conditions are checked as part of the resolution, no matter what you do to try to stop it.
3) After the charge has been resolved. The minotaur charges and you put some iron behind it. The minotaur's attack of opportunity has a chance to disrupt your spell. What exactly were you going for, here?

You cannot do it:

4) Between the check and the resolution. The check happens during the resolution, so you can't interrupt the action partway through.
5) During the resolution. Movement isn't divided up into stages you can interrupt - Zeno need not apply.

Whether you actually like that answer or not, is up to you. But be prepared for "But the rules say..." if the tables are turned and the PCs in another group want to charge your artificer.

Neither D&D 3.5 nor Pathfinder have action declarations as a separate part of taking an action. Older editions of D&D had it because the kind of action you were taking affected the turn order in combat, but that is a thing of the past.

You still need to tell the DM what kind of action you're performing (for the sake of communication and a smoothly running game), but it doesn't have any meaning within the game rules. Other characters cannot magically sense your intentions (at least, not without actual magic) or attempt to interrupt your turn based on knowledge you give to your DM about what your character is about to do.

Unless your character is actually declaring out loud what actions they're going to take before they do them for all the world to hear.

[Necroticplague]

Neither D&D 3.5 nor Pathfinder have action declarations as a separate part of taking an action. Older editions of D&D had it because the kind of action you were taking affected the turn order in combat, but that is a thing of the past.

You still need to tell the DM what kind of action you're performing (for the sake of communication and a smoothly running game), but it doesn't have any meaning within the game rules. Other characters cannot magically sense your intentions (at least, not without actual magic) or attempt to interrupt your turn based on knowledge you give to your DM about what your character is about to do.
If you don’t need any form of action declaration, then how does this part of readied actions work?

. Then, any time before your next action, you may take the readied action in response to that condition. The action occurs just before the action that triggers it.
If you don’t declare an action in some way, how can you be reacting to something that hasn’t happened yet (and, depending on your action, may not be able to happen), given that readied actions occur before their trigger?

[KillianHawkeye]

If you have an action readied, you've put yourself into a state of heightened suspension. You're in a position to enact your plan at a moment's notice and you're keenly watching for something specific to trigger your action. The triggering of a readied action is not based on someone else "declaring" an action that matches your triggering condition, it's based on your character's ability to observe such an action in progress.

Readying is classified as a "special initiative action", and it works the way it works because that was the simplest way the designers could think of to integrate out-of-turn actions into a turn-based system. Taking a readied action does not negate the action that triggered it (unless your action makes it impossible, such as by killing or incapacitating the target), even though it technically resolves beforehand.

[DeltaEmil]

Personally, I wouldn't let the minotaur take any damage, and simply end its movement.
Spellcasters are already extremely powerful and do have tons of other movement-restricting or blocking spells that can also deal damage anyway. Now, if the spellcaster was readying its action to cast the wall of iron, and an ally of it would then use its readied action to topple the wall upon the charging minotaur to deal damage, that would be good, because it would also mean that two player characters are acting together as a team to defeat the enemy, instead of just having a spellcaster dominate the fight once again all by itself.

[Crake]

If you don’t need any form of action declaration, then how does this part of readied actions work?

If you don’t declare an action in some way, how can you be reacting to something that hasn’t happened yet (and, depending on your action, may not be able to happen), given that readied actions occur before their trigger?

If that were the case then you could never interrupt spellcasters, because you either fire before they start spellcasting, or after they finish.

[Jormengand]

If that were the case then you could never interrupt spellcasters, because you either fire before they start spellcasting, or after they finish.

Damage which takes place between the declaration and the resolution interrupts spellcasters. But you can't interrupt a caster when they've fired three of their five magic missiles, only between them attempting to cast the spell and actually doing so.

[Crake]

Damage which takes place between the declaration and the resolution interrupts spellcasters. But you can't interrupt a caster when they've fired three of their five magic missiles, only between them attempting to cast the spell and actually doing so.

So you're agreeing with me that there is a period of time between the start of an action and it's conclusion? Cool, thanks.

[Jormengand]

So you're agreeing with me that there is a period of time between the start of an action and it's conclusion? Cool, thanks.

Yes, effectively. You're just calling them "Start" and "Conclusion" which is confusing because it implies you can interrupt someone during a multiple-shot spell or otherwise partway through the resolution of the action, and I'm calling them "Declaration" and "Resolution" which is only confusing if you take "Declaration" to mean "Shouting out the name of your attack(/movement/whatever) before you make it."

[KillianHawkeye]

But you can't interrupt a caster when they've fired three of their five magic missiles, only between them attempting to cast the spell and actually doing so.

This is primarily because all of the magic missiles get fired off simultaneously. To contrast, you definitely could (with the right readied action trigger) interrupt an archer between their second and third bow shot.

[Jormengand]

This is primarily because all of the magic missiles get fired off simultaneously. To contrast, you definitely could (with the right readied action trigger) interrupt an archer between their second and third bow shot.

This is true, but only because of perculiar wording in the full attack description itself:

"You do not need to specify the targets of your attacks ahead of time. You can see how the earlier attacks turn out before assigning the later ones."

That is, there are multiple declarations and multiple resolutions, unlike movement, where you declare the entire thing at once and resolve the entire thing at once and if someone puts a wall in your way, you don't collide with it.

[Crake]

That is, there are multiple declarations and multiple resolutions, unlike movement, where you declare the entire thing at once and resolve the entire thing at once and if someone puts a wall in your way, you don't collide with it.

Where does it say that you need to declare your entire movement beforehand? Quite often my table moves pieces square by square, and sometimes that can be NECESSARY when, for example, turning a corner around which you have no idea what the environment is like.

[Jormengand]

Where does it say that you need to declare your entire movement beforehand? Quite often my table moves pieces square by square, and sometimes that can be NECESSARY when, for example, turning a corner around which you have no idea what the environment is like.

Counter-question: Why WOULD you be allowed to decide partway through your movement that you don't like the direction you're moving in and want to do a 180 flip? There's nothing apart from the full attack text specifying that you can decide you don't like how your full attack's panning out and change it that implies that you can change what an action does partway through (or that "Partway through" is meaningful). Why would the full attack text be there if it were possible to do that on any action, anyway? Move is "Move your speed" not "Move half your speed, have a think for a minute, and move half your speed again." Plus, in specific with charges (which are what's ostensibly being discussed) there's only one position you can move to, unless you're saying you can do a 180 flip and charge someone else when the wall of iron comes down?

[KillianHawkeye]

That is, there are multiple declarations and multiple resolutions, unlike movement, where you declare the entire thing at once and resolve the entire thing at once and if someone puts a wall in your way, you don't collide with it.

I am not nor have I ever been an advocate of the position that the minotaur would collide with the wall and take damage. What I have been saying is that actions are not instantaneous and are in fact interruptible provided they are observable.

I also disagree with your assertion that movement is resolved all at once, because there are numerous scenarios in which a character can begin moving and then something interrupts them part-way to their destination. These can include a readied action for when an enemy comes into sight or when one comes to within a certain range, or can be ordinary dangers such as walking down a hallway and triggering a trap. The point is, movement is easily demonstrated to be an action which can be partially interrupted.


In the case of Minotaur vs Conjured Wall, the easiest way to rule the outcome is to downgrade the minotaur's charge action to a move action (or a double move if the distance he already traveled was in excess of his movement speed). He begins to charge, but then stops because he cannot complete. He does not collide with the wall because he can stop short. If he has any actions remaining, he should be allowed to do something else. I would even allow him to begin moving in another direction if he still has movement left. This tactic is useful for defense, but it won't cause any damage to the minotaur. At worst, you make him waste his turn.

Alternatively, the minotaur could choose to make his charge attack against the wall itself if it thinks it has any chance of breaking through it.

[Crake]

Counter-question: Why WOULD you be allowed to decide partway through your movement that you don't like the direction you're moving in and want to do a 180 flip? There's nothing apart from the full attack text specifying that you can decide you don't like how your full attack's panning out and change it that implies that you can change what an action does partway through (or that "Partway through" is meaningful). Why would the full attack text be there if it were possible to do that on any action, anyway? Move is "Move your speed" not "Move half your speed, have a think for a minute, and move half your speed again." Plus, in specific with charges (which are what's ostensibly being discussed) there's only one position you can move to, unless you're saying you can do a 180 flip and charge someone else when the wall of iron comes down?

I agree that charges are a specific case, because they have a set end position, and very strict conditions to make them possible, you must be able to see your target and have no obstructions along the way etc, but for regular movement... well, that's just how normal people function? If you're walking in a dark dungeon and you come across a corner? Oh no, too bad, your declared movement was to keep going forward, so you're walking into the wall now, sorry. No? You're right, it says move your move speed, and that's all it says. You can walk around a corner, spending half your move speed, only to see a giant monster, and decide, you want to spend the rest of your move speed going the opposite direction, or you might walk into an invisible wall and instead spend the rest of your movement following the wall along to see where it goes. You don't just magicall start at A, and then teleport to B, there's a whole series of walking happening along the way that can be interrupted or changed with new information or circumstances.

[Jormengand]

I am not nor have I ever been an advocate of the position that the minotaur would collide with the wall and take damage. What I have been saying is that actions are not instantaneous and are in fact interruptible provided they are observable.

I also disagree with your assertion that movement is resolved all at once, because there are numerous scenarios in which a character can begin moving and then something interrupts them part-way to their destination. These can include a readied action for when an enemy comes into sight or when one comes to within a certain range, or can be ordinary dangers such as walking down a hallway and triggering a trap. The point is, movement is easily demonstrated to be an action which can be partially interrupted.

You can certainly ready an action to shoot on sight, which will happen when the movement is done. You can also trigger a trap as part of your movement, which will shoot you once you're done (which is exactly how it would work in real life: you would not be in the position you were in when you set the trap off by the time the arrows it launched reached you). You can be struck or even stopped by specific exceptions (notably attacks of opportunity, especially stand still), but other than that, zeno need not apply.


In the case of Minotaur vs Conjured Wall, the easiest way to rule the outcome is to downgrade the minotaur's charge action to a move action (or a double move if the distance he already traveled was in excess of his movement speed). He begins to charge, but then stops because he cannot complete. He does not collide with the wall because he can stop short. If he has any actions remaining, he should be allowed to do something else. I would even allow him to begin moving in another direction if he still has movement left. This tactic is useful for defense, but it won't cause any damage to the minotaur. At worst, you make him waste his turn.

Alternatively, the minotaur could choose to make his charge attack against the wall itself if it thinks it has any chance of breaking through it.

Honestly, if I were houseruling it, quite apart from making zeno slightly happier, I'd probably make it so that the minotaur did run into the wall, though probably not for any substantial amount of damage (have you ever run into a wall? Did it knock you out or stagger you? No? Then it probably did less than 3 damage).

[KillianHawkeye]

Also, it's worth remembering that despite the turn-based abstraction of combat in D&D, in the reality that your characters experience everything is pretty much all happening at once. Real combat is a chaotic mess. Everyone is taking simultaneous turns every six seconds while reacting to the ever-changing situation.


EDIT:

You can certainly ready an action to shoot on sight, which will happen when the movement is done.

Okay, no. This is where you are wrong. Readied actions complete immediately when they are triggered, before the triggering action is resolved. That's right there in the rules.


You can also trigger a trap as part of your movement, which will shoot you once you're done (which is exactly how it would work in real life: you would not be in the position you were in when you set the trap off by the time the arrows it launched reached you).

This is still wrong because of the above, but suppose it's a pit trap. You fall into it (assuming a failed Relfex save) or stop moving at the edge (if you succeed) regardless of where you intended to finish your move action. Movement interrupted.

[Jormengand]

I agree that charges are a specific case, because they have a set end position, and very strict conditions to make them possible, you must be able to see your target and have no obstructions along the way etc, but for regular movement... well, that's just how normal people function? If you're walking in a dark dungeon and you come across a corner? Oh no, too bad, your declared movement was to keep going forward, so you're walking into the wall now, sorry. No? You're right, it says move your move speed, and that's all it says. You can walk around a corner, spending half your move speed, only to see a giant monster, and decide, you want to spend the rest of your move speed going the opposite direction, or you might walk into an invisible wall and instead spend the rest of your movement following the wall along to see where it goes. You don't just magicall start at A, and then teleport to B, there's a whole series of walking happening along the way that can be interrupted or changed with new information or circumstances.

I'm sorry, but if I'm moving at a sort of combat hustle (5 ft per second is only walking speed if you've got a fairly significant inertia) and something unexpected happens, what I do is stumble forwards a few steps more, not twirl about on the spot and walk calmly back around to react to the change in circumstances.

Second, the rules specify what you can do, not what you cannot do. It doesn't need to say you can't change direction halfway through a movement any more than it needs to say that you can't use magic missile to knock people on buildings - irrespective of whether it's a natural assumption that it would do that, the rules don't have to say you can't because they never implied you could.


Okay, no. This is where you are wrong. Readied actions complete immediately when they are triggered, before the triggering action is resolved. That's right there in the rules.

That's true if they're triggered by the declaration, but not if they're triggered by the resolution. If someone fires a magic missile at you and that triggers a readied action "When I take damage", there's no way that can happen before the triggering action is resolved. Similarly if someone moves and triggers a readied action "When a creature I can see moves", if you can already see them, it triggers after the declaration, but if you can't, it triggers after the resolution.


This is still wrong because of the above, but suppose it's a pit trap. You fall into it (assuming a failed Relfex save) or stop moving at the edge (if you succeed) regardless of where you intended to finish your move action. Movement interrupted.

That's another specific trumps general, yes.

[KillianHawkeye]

There's still no such thing as a declaration of actions within the game mechanics, but it's late and I'm clearly not going to get through to you. Whatever, surely the OP has heard enough to make up his own mind by now.

[Jormengand]

There's still no such thing as a declaration of actions within the game mechanics, but it's late and I'm clearly not going to get through to you. Whatever, surely the OP has heard enough to make up his own mind by now.

It's not called that, no. But you still have to decide what action you're going to do, and once you've done that, then readied actions can happen. This is why you can interrupt someone who attempts an action before the action proper has resolved.

[Crake]

30ft per round, or 3 miles per hour is a very casual walk speed. Even hustling at double movement speed is a casual jog, and yes, you can quite often stop a jog on a dime and run away if someone suddenly starts waving a knife in your face. Unless you're incredibly unfit and can't even stop your own inertia within 5ft that is.

[Doctor Awkward]

If the minotaur charges towards the artificer, and along the way moves through an allied Monk's threatened space, provoking an attack of opportunity, and then fails his Fortitude save against the Monk's stunning fist, where does the minotaur stop?

He stops immediately in his tracks in the square he got stunned. Or if that square is illegal for him to be in, then he stops in his last legal square (http://www.d20srd.org/srd/combat/movementPositionAndDistance.htm#specialMovementRul es) before he got stunned)

Why would a readied action of "If that minotaur charges me I'm dropping a wall in front of him" work any differently?

[Jormengand]

If the minotaur charges towards the artificer, and along the way moves through an allied Monk's threatened space, provoking an attack of opportunity, and then fails his Fortitude save against the Monk's stunning fist, where does the minotaur stop?

He stops immediately in his tracks in the square he got stunned. Or if that square is illegal for him to be in, then he stops in his last legal square (http://www.d20srd.org/srd/combat/movementPositionAndDistance.htm#specialMovementRul es) before he got stunned)

Why would a readied action of "If that minotaur charges me I'm dropping a wall in front of him" work any differently?

Because readied actions occur "Just before the action that triggers it". The action, here, is the "Charge" action. The wall comes down just before the charge action. The charge becomes an illegal action and fails.

Attacks of opportunity, including those made using feats such as Stunning Fist or Stand Still, take place, among other times, when a creature is "Moving out of a threatened square". If stunning fist is used, the creature takes some damage, drops everything it's holding, finishes its movement (it's already taken the move action, and stunning fist doesn't stop you moving, only from taking actions, but you already did that while you weren't stunned. Note that I would never actually rule this to be the case in real play) and then stands there, stunned. If the attack used is Stand Still, the foe will "Immediately halt", which really does interrupt its movement partway through.

[Doctor Awkward]

Because readied actions occur "Just before the action that triggers it".

Not always they don't. (http://www.d20srd.org/srd/combat/specialInitiativeActions.htm#ready) It depends entirely on the trigger chosen by the readying character:


You can ready a standard action, a move action, or a free action. To do so, specify the action you will take and the conditions under which you will take it. Then, any time before your next action, you may take the readied action in response to that condition. The action occurs just before the action that triggers it. If the triggered action is part of another character’s activities, you interrupt the other character. Assuming he is still capable of doing so, he continues his actions once you complete your readied action.

Placing a wall in front of a charging character blocks line of sight. Without line of sight you can no longer legally charge. You have interrupted the charger, and ruined his action.




The action, here, is the "Charge" action. The wall comes down just before the charge action. The charge becomes an illegal action and fails.

Attacks of opportunity, including those made using feats such as Stunning Fist or Stand Still, take place, among other times, when a creature is "Moving out of a threatened square". If stunning fist is used, the creature takes some damage, drops everything it's holding, finishes its movement (it's already taken the move action, and stunning fist doesn't stop you moving, only from taking actions, but you already did that while you weren't stunned. Note that I would never actually rule this to be the case in real play) and then stands there, stunned. If the attack used is Stand Still, the foe will "Immediately halt", which really does interrupt its movement partway through.

The Player's Handbook directly contradicts you in the example it gives for resolving the situation of ending your movement in an illegal square (which is where I got my hypothetical from):


Sometimes
a character ends its movement while moving through a space
where it’s not allowed to stop. For example, you might incur an
attack of opportunity from a monk while moving through a friend’s
square and become stunned. When that happens, put your
miniature in the last legal position you occupied, or the closest legal
position, if there’s a legal position that’s closer.

[RazorChain]

An artificer holds an action, to summon a wall of iron in the path of a charging minotaur.

What do?

Simple, velocity doesn't exist in D&D. This can be seen in the falling rules, the only thing that matters is how far you fall, not the speed. Everybody knows in the real world the farther you fall the more speed you'll pick up until you reach terminal velocity.

So what to do is simple, the rules have already dictated that distance equals damage. The more distance the minotaur has traveled the more damage he takes, so if he ran 100' then he'll take 10d6 damage when he impacts on the wall of iron.