DM calls for an ability check when a character or monster attempts an action (other than an attack) that has a chance of failure
In that case, strictly we should be doing an ability check then roleplaying the result. That's fine, too, I do that at times. However, if you are going to allow roleplay before the check, I would argue that the attempt comes after the roleplay, otherwise the check should already have been called and rolled. If the check hasn't been called, then the attempt hasn't yet happened.
Note that none of this is me agreeing with the way the OP's DM is operating. RP can be incorporated into the checks, but should be done in a manner appropriate for the group and/or individual player.
Again, if you go by RAW, this is a clear case of a clever action providing advantage.
I completely disagree. Trying to lift or drag a boulder with your bare hands is a completely different task to doing so with a block and tackle. Depending on the circumstances, using the block and tackle could easily make it an automatic success, or make it possible to lift something which would have been an automatic failure.
Would you say that lifting a pallet yourself is the same as doing so using a forklift truck? Using an axe to chop down a tree is the same as trying to gnaw your way through it with your teeth? They are completely different tasks and should be assigned a different DC, because one is much more difficult than the other. They may even involve a different skill.
But like mentioned before, making a distinction from player's skill would mean that their tone of voice, the cadence, face mimics and general flow will not be taken into consideration. That is what Persuasion roll takes care of.
I agree with that in most cases. But that would also mean that, if a player's skill in determining which lie to tell is less than that of their character, there will be times you need to consider that, too, and let the dice decide whether the player hit on the correct lie.
I feel like at this point it's arguing for arguing's sake. Just say that at one table you would give disadvantage while at the other it would be higher DC and be done with it.
It's not so much the technical medium than the reason for increasing the DC that bugs me. Because the reason invoked is that the player was not the best one around the table at roleplay, and that strikes me as incredibly unfair to friends playing the game together, some of which might be salesmen and other autists, in a collaborative game where everyone should be allowed to play exactly what they want as long as it does not make someone else inconfortable.
I've seen someone ask why do we accept a declaration "I walk stealthily to the merchant's house" but do not accept "I try to deceive the guard".
The difference is practicality. D&D is in it's core a game of words. We speak about our actions and we speak as our characters. It is infinitely easier to say which lie we try to sell the guard than for the DM to whip out a 3D map of the whole town with ALL the guards with their cones of sight and patrol routes and say to the player "tell me where you are going".
And because it's a game of words, as you say, should you be allowed to do two things that really bug me:
Discriminate amongst your friends based on fluency of speech ?
As a side note, I have played in english which is not my mother tongue, and I'm really happy that my american, english and australian friends did not discriminate my characters based on my french accent and english fluency...
Allow people who are extremely fluent to deceive guards better than other people when they have a dumped CHA of 8 and no proficiency, contrary to the other characters ? I'm sorry, but this is absolutely contrary to the principle of roleplaying, which is describing what your character would do and say based on his abilities and description...
This is why it is not unreasonable to ask the player what lie exactly are they trying to tell but it is unreasonable to demand that they know exactly which route to take while stealthing when we usually don't give them a full map with all streets and guard posts anyway.
Of course, you can and should make shortcut where needed because of material difficulties, but you should not make any based on your friend's real abilities (compared to their characters) ?
They can say something super clever that will give them advantage or something so incredibly stupid that no roll will be granted. This is part of the game and part of making awesome memories at the table.
And that is absolutely fine.
But like mentioned before, making a distinction from player's skill would mean that their tone of voice, the cadence, face mimics and general flow will not be taken into consideration. That is what Persuasion roll takes care of.
Except if you set different DCs based on what you mentioned above, which is where the unfairness comes into play, at both of the levels above.
IDK how you read my post but I specifically said that I don't discriminate based on fluency of speech. Nor do I increase the DC or give disadvantage.
If a player says something stupid, they get disadvantage. It's D&D, players always say something stupid. If they say something clever, they get advantage. I don't care if they use simple language, stutter, mispronounce or miss words etc. I just want to know what they are saying. It doesn't even have to be in 1st person.
They can say "I will tell the guard that I've seen his mother fall down, he should probably check up on her". I don't care how eloquently they say that, how many emms and umms are in the sentence and so on.
IDK how you read my post but I specifically said that I don't discriminate based on fluency of speech. Nor do I increase the DC or give disadvantage.
Then you see the limits of my own fluency, I did not see it that plainly in your post, but we are then in agreement.
If a player says something stupid, they get disadvantage. It's D&D, players always say something stupid. If they say something clever, they get advantage. I don't care if they use simple language, stutter, mispronounce words etc. I just want to know what they are saying.
How about using third person speech ? Because, again, some players, in particular beginners but not always, are not comfortable speaking in character ? "My character bribes the guard so that he lets us pass ?"
And how about roleplay appropriate to the character ? I mean, the assassin with 8 CHA and no proficiency in deception trying to BS a guard, but with a salesman player in full swing ? What do you do then ?
I edited my previous post about 3rd person speech.
As for what to do when a player's natural skill exceeds their characters (in this case Charisma) - well, that is a discussion that needs to be had with the player.
Occasional flashes of brilliance when a player's flair makes up for their character's lack of Charisma are fine but at some point I will take the player aside and ask them how they think their dump stat manifests in their character.
Just like we expect characters with extremely low Int to be RPed correctly (meaning, no differential equations even if they player knows them), we should expect a low Cha character be portrayed accordingly.
Anyway, yes, 3rd person speech is fine with me. They can say "I/My char will try to convince the guard that I/he saw his mother fall sick, maybe he should check on her" - I don't care how many umms, emms and errs are in that sentence, how fluent it is etc.
Oh, and when I say that a low Cha needs to be portrayed accordingly I don't mean that the player should suddenly turn into an actor and perfectly play someone with lower skillset than they have. It can manifests in different ways, from descriptive language ("my char will timidly try to say this etc") to DM intervention ("the speech that sounded perfect in your mind didn't quite hit the tones you imagined").
There is no mechanical difference between modifying the roll and modifying the DC. Giving a +2 to the roll is identical to reducing the DC by 2.
The DC is absolutely fixed by the design
In a written module/adventure where they have fixed the DC by design, you are right. In an unwritten adventure, or in a circumstance not fixed in the module's design, the DC is up to the DM to decide. Whether he uses circumstance to adjust the DC, apply modifiers to the roll, give advantage or disadvantage or rule that the action is impossible or an automatic success doesn't really matter.
OTOH, using the quality of roleplay/acting or other skills of the player (rather than the character) to determine those things is a completely different story.
I am in no way wanting to make players better roleplayed or any such. It isn't the qualify of the roleplaying, but the specifics of the situation which count to adjust the difficulty of the task. Whether you are using a rusty or sharp axe to chop down a tree changed how difficult it is. Using a ladder to climb a wall or just trying to scale it without equipment makes a difference to how difficult it is. Using a battering ram makes it easier to break through a door than just running at it. Using a forged order makes it easier to get past a guard than simply telling the guards that you have permission from a specific officer, which in turn is easier than trying to convince them you have permission with no details.
All of these affect the difficulty of the task. They could be applied using advantage or disadvantage, modifiers to the roll, or just by making it part of the DC when you call for the roll. It doesn't matter, unless you are using a written adventure with fixed, printed DCs. If the DM is deciding on the DC, they can incorporate these factors into it when making that decision.
"The world sets the DC, the players' actions through their character make the roll"
Great. So, the "world" contains a wall, which the players want to climb. The world contains ladders. Climbing the wall with a ladder is really easy, so I would probably set that as a DC 2: It's possible that they could fall off the ladder or knock it over while climbing, but not very likely.
However, by the players' decision, they choose not to use a ladder. Instead, they want to climb it without any equipment. But the DC is already set as 2, so we give them disadvantage... But seeing as they have a +2 modifier, they automatically pass the check even with disadvantage. They get to climb that wall as an automatic success, because the world set the DC.
Or you could have gone the other way, and set the DC without the ladder. It's a smooth wall, so it's pretty difficult to climb, and we set the DC as 15. They decide to use the ladder they saw around the corner, so you give them advantage. With that same +2 modifier, they have around a 1 in 3 chance of failing to climb to the top of a ladder. (EDIT: Sorry, brain fart, got my words muddled)
Like it or not, the specific circumstances alter the difficulty of achieving a goal, and the character's actions affect those circumstances. They need to be factored in.
There is no mechanical difference between modifying the roll and modifying the DC. Giving a +2 to the roll is identical to reducing the DC by 2.
This is only true if you are not using the Advantage / Disadvantage mechanic, which is the core the the system as a reminder, the purpose was to limit the number of modifiers to juggle.
I’m sorry, but that’s not correct. Rolling twice doesn’t change the fact that the calculation of the odds is functionally identical. The odds of success with advantage are equal to ((the odds of success times (1 minus the odds of success) times two) plus (the odds of success squared)). Given that the odds of success are the same whether you manipulate the roll or the DC, the formula shows that advantage is not affected by this either.
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"these b...d brought a ladder, I did not think of that, it's too easy for them, therefore the wall is going to be harder to get over because otherwise it's a cakewalk, etc."
Bot that's my point: Bringing a ladder, the actions of the PC, changes the task and, therefore, the difficulty. You should be changing the difficulty of getting over the wall: It's an almost certain success to get over a wall with a long enough ladder. Similarly, if you had set the DC of climbing over a wall using a ladder which is already there, but the PC decides not to use that ladder, it's a more difficult task. Using the same DC for both is ridiculous.
1) The problem is that you are atomising the task too much for me, and I think for 5e in general. The task should simply be "getting over the wall". That's it. It does not change according to anything, it's just an inherent characteristic of the wall. This is the way it is presented in all publications and modules, and, once more, 5e NEVER tells you to modify the DC.
2) The DM should be thinking things like "They were clever enough to bring a ladder, good for them ! I will make sure to point out how great an idea that was and how simpler it made it for them to infiltrate the palace".
1) DMG p. 244, Tracking DCs: +5/day since the creature passed, -5 if it left a trail. Also p. 244, a creature’s attitude determines the DC for getting a reaction, and players can change that attitude over the course of a conversation “if the adventurers say or do the right thing”.
2) “made it simpler” is exactly the same as saying “lowered the difficulty class”
"Why do you need to complicate things and change a DC for something that has become trivial."
Why do you need to complicate things and set a DC for something so trivial, or something they may never even do?
At the end of the day, these two approaches are mechanically identical until you consider advantage/disadvantage, which can be applied either way. There is no difference between deciding climbing a wall is DC 20, then giving them a +15 to their roll because they brought a ladder, and waiting to see how they plan to climb the wall and deciding it should be a DC 5. In that case, you have waited to see exactly what action they want to take (in this case, climb a wall by hand or place a ladder against it and climb that) before deciding whether it has a chance of failure and, therefore, calling for an ability check.
Taking this even further: You know there is a wall for them to get past, and have decided in advance that it is a DC 15 to get to the other side. They then talk to a local band of mercenaries and have them use a catapult to knock the wall down. When you get there... You've already fixed the DC at 15 to get to the other side of the wall, so it's a DC 15 and always will be... even though the wall no longer stands and they can just walk across the rubble.
Once again, this is not about the quality of roleplay or anything like that. This is deciding the difficulty of what the player chooses to do.
Can you please take into account that the difficulty of an action is DIFFERENT from the DC of the task of "getting over the wall" ?
How is there a single DC for a task, regardless of how that task is performed? How is the DC for getting over a wall always X if I might fly over it without effort whatsoever, or climb over it with a bit of effort, or decide to demolish the wall with a lot of effort? Or maybe the better question is, why are you setting a DC for “getting over the wall” when in practice you’ll only use the DC for how the PCs choose to try and get over the wall?
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'(and this is in the PH contrary to "modifying a DC")'
This isn't modifying a DC, it is setting a DC. It's just that you want to set a DC in advance before the PC has decided what action they are going to take, whereas I want to see what the PC is going to do before I call for the check, decide how difficult that course of action will be and set the DC.
1) The problem is that you are atomising the task too much for me, and I think for 5e in general. The task should simply be "getting over the wall". That's it. It does not change according to anything, it's just an inherent characteristic of the wall. This is the way it is presented in all publications and modules, and, once more, 5e NEVER tells you to modify the DC.
2) The DM should be thinking things like "They were clever enough to bring a ladder, good for them ! I will make sure to point out how great an idea that was and how simpler it made it for them to infiltrate the palace".
1) DMG p. 244, Tracking DCs: +5/day since the creature passed, -5 if it left a trail.
1) Perfectly fine, this has nothing to do with players' actions, it's just helping the DM set the initail DC for tracking.
Also p. 244, a creature’s attitude determines the DC for getting a reaction, and players can change that attitude over the course of a conversation “if the adventurers say or do the right thing”.
2) They change the attitude, that's fine, the NEXT task will be easier with a different DC. But it certainly does not retroactively modify the DC of changing the attitude in the first place.
1) Yes, but it shows that the DMG specifically suggests changing the DC based on circumstances. You claimed 5E never does that.
2) So DCs can be changed, and the official 5E ruleset explains this. That’s the point. Whether it does so retroactively or not isn’t pertinent to whether it does in the first place.
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"Why do you need to complicate things and change a DC for something that has become trivial."
Why do you need to complicate things and set a DC for something so trivial, or something they may never even do?
If they are not even approaching the wall, either the DC is in the module and it's just there, or you have not foreseen it and you will just never set a DC because the task of "getting over the wall' is never undertaken.
At the end of the day, these two approaches are mechanically identical until you consider advantage/disadvantage, which can be applied either way. There is no difference between deciding climbing a wall is DC 20, then giving them a +15 to their roll because they brought a ladder, and waiting to see how they plan to climb the wall and deciding it should be a DC 5. In that case, you have waited to see exactly what action they want to take (in this case, climb a wall by hand or place a ladder against it and climb that) before deciding whether it has a chance of failure and, therefore, calling for an ability check.
Taking this even further: You know there is a wall for them to get past, and have decided in advance that it is a DC 15 to get to the other side. They then talk to a local band of mercenaries and have them use a catapult to knock the wall down. When you get there... You've already fixed the DC at 15 to get to the other side of the wall, so it's a DC 15 and always will be... even though the wall no longer stands and they can just walk across the rubble.
Again, see how absurd you have to make the examples ? the DC 15 would be for the task "get over the wall". If there is no wall, why would there be a task ?
Once again, this is not about the quality of roleplay or anything like that. This is deciding the difficulty of what the player chooses to do.
Deciding the difficulty is NOT the same thing as the Difficulty Class of the task. I will make it simple. Let's say that you have taken into account the player's actions and set a DC based on this. Do we agree that the difficulty will not be the same to the barbarian who has advantage on his athletics check and for the wizard who has not ? Or simply not the same for a barbarian who has +8 and a wizard who has +2 ? In that case are you modifying the DC ? No, you are just applying modifiers, which change the difficulty of succeeding at the task but you are (I hope) not changing the DC !
Setting the DC is DM dependent RAW. Period. You can change it at will if you want and there is nothing wrong with that.
Setting the DC is DM dependent RAW. Period. You can change it at will if you want and there is nothing wrong with that.
That's your opinion, and it obviously is fine in your game if your players are happy with it, however, my opinion is different, I think that setting the DC based on players actions is bad for the players and I've written at length why I think it is. You can hammer your opinion like this all you want, it does not make it more true or more justified.
In particular, I think a number of us agree that it is really bad to set the DC based on the quality of the roleplaying of a given player. Of course, as a DM you can do this, but I happen to think that it's unfair to your players, and I've explained why.
Not opinion as its written as such in the book. You can choose to do whatever with it but please do not shame people for following the book.
I have. If the only mechanic to be used is advantage/disadvantage, then you get ridiculous state whereby you have a 1 in 3 chance of not being able to climb to the top of a ladder. If you use absolute modifiers, too, then there is no mechanical difference between that and modifying the DC based on actions.
Please note, for me, the DC is set, not modified, at the time a player wishes to do something. You are just setting that DC earlier, before the player has finished telling you what they want to do.
"Again, see how absurd you have to make the examples ?the DC 15 would be for the task "get over the wall". If there is no wall, why would there be a task ?"
The examples are "absurd" to illustrate the absurdity of setting a DC in advance without taking into account the circumstances. We can modify it slightly: what if the mercs had knocked most of the wall down, but there was still a knee-high wall to get over? Is that still a DC 15 to "get over the wall"? That's absurd!
"Do we agree that the difficulty will not be the same to the barbarian who has advantage on his athletics check and for the wizard who has not ?"
No, the difficulty of the task is the same, the barbarian is just better at it. That's modifying for the character's abilities, not their actions nor the circumstances surrounding the action.
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In that case, strictly we should be doing an ability check then roleplaying the result. That's fine, too, I do that at times. However, if you are going to allow roleplay before the check, I would argue that the attempt comes after the roleplay, otherwise the check should already have been called and rolled. If the check hasn't been called, then the attempt hasn't yet happened.
Note that none of this is me agreeing with the way the OP's DM is operating. RP can be incorporated into the checks, but should be done in a manner appropriate for the group and/or individual player.
I completely disagree. Trying to lift or drag a boulder with your bare hands is a completely different task to doing so with a block and tackle. Depending on the circumstances, using the block and tackle could easily make it an automatic success, or make it possible to lift something which would have been an automatic failure.
Would you say that lifting a pallet yourself is the same as doing so using a forklift truck? Using an axe to chop down a tree is the same as trying to gnaw your way through it with your teeth? They are completely different tasks and should be assigned a different DC, because one is much more difficult than the other. They may even involve a different skill.
I agree with that in most cases. But that would also mean that, if a player's skill in determining which lie to tell is less than that of their character, there will be times you need to consider that, too, and let the dice decide whether the player hit on the correct lie.
IDK how you read my post but I specifically said that I don't discriminate based on fluency of speech. Nor do I increase the DC or give disadvantage.
If a player says something stupid, they get disadvantage. It's D&D, players always say something stupid. If they say something clever, they get advantage. I don't care if they use simple language, stutter, mispronounce or miss words etc. I just want to know what they are saying. It doesn't even have to be in 1st person.
They can say "I will tell the guard that I've seen his mother fall down, he should probably check up on her". I don't care how eloquently they say that, how many emms and umms are in the sentence and so on.
I edited my previous post about 3rd person speech.
As for what to do when a player's natural skill exceeds their characters (in this case Charisma) - well, that is a discussion that needs to be had with the player.
Occasional flashes of brilliance when a player's flair makes up for their character's lack of Charisma are fine but at some point I will take the player aside and ask them how they think their dump stat manifests in their character.
Just like we expect characters with extremely low Int to be RPed correctly (meaning, no differential equations even if they player knows them), we should expect a low Cha character be portrayed accordingly.
Or I thought I did edit.
Anyway, yes, 3rd person speech is fine with me. They can say "I/My char will try to convince the guard that I/he saw his mother fall sick, maybe he should check on her" - I don't care how many umms, emms and errs are in that sentence, how fluent it is etc.
Oh, and when I say that a low Cha needs to be portrayed accordingly I don't mean that the player should suddenly turn into an actor and perfectly play someone with lower skillset than they have. It can manifests in different ways, from descriptive language ("my char will timidly try to say this etc") to DM intervention ("the speech that sounded perfect in your mind didn't quite hit the tones you imagined").
There is no mechanical difference between modifying the roll and modifying the DC. Giving a +2 to the roll is identical to reducing the DC by 2.
In a written module/adventure where they have fixed the DC by design, you are right. In an unwritten adventure, or in a circumstance not fixed in the module's design, the DC is up to the DM to decide. Whether he uses circumstance to adjust the DC, apply modifiers to the roll, give advantage or disadvantage or rule that the action is impossible or an automatic success doesn't really matter.
OTOH, using the quality of roleplay/acting or other skills of the player (rather than the character) to determine those things is a completely different story.
I am in no way wanting to make players better roleplayed or any such. It isn't the qualify of the roleplaying, but the specifics of the situation which count to adjust the difficulty of the task. Whether you are using a rusty or sharp axe to chop down a tree changed how difficult it is. Using a ladder to climb a wall or just trying to scale it without equipment makes a difference to how difficult it is. Using a battering ram makes it easier to break through a door than just running at it. Using a forged order makes it easier to get past a guard than simply telling the guards that you have permission from a specific officer, which in turn is easier than trying to convince them you have permission with no details.
All of these affect the difficulty of the task. They could be applied using advantage or disadvantage, modifiers to the roll, or just by making it part of the DC when you call for the roll. It doesn't matter, unless you are using a written adventure with fixed, printed DCs. If the DM is deciding on the DC, they can incorporate these factors into it when making that decision.
"The world sets the DC, the players' actions through their character make the roll"
Great. So, the "world" contains a wall, which the players want to climb. The world contains ladders. Climbing the wall with a ladder is really easy, so I would probably set that as a DC 2: It's possible that they could fall off the ladder or knock it over while climbing, but not very likely.
However, by the players' decision, they choose not to use a ladder. Instead, they want to climb it without any equipment. But the DC is already set as 2, so we give them disadvantage... But seeing as they have a +2 modifier, they automatically pass the check even with disadvantage. They get to climb that wall as an automatic success, because the world set the DC.
Or you could have gone the other way, and set the DC without the ladder. It's a smooth wall, so it's pretty difficult to climb, and we set the DC as 15. They decide to use the ladder they saw around the corner, so you give them advantage. With that same +2 modifier, they have around a 1 in 3 chance of failing to climb to the top of a ladder. (EDIT: Sorry, brain fart, got my words muddled)
Like it or not, the specific circumstances alter the difficulty of achieving a goal, and the character's actions affect those circumstances. They need to be factored in.
I’m sorry, but that’s not correct. Rolling twice doesn’t change the fact that the calculation of the odds is functionally identical. The odds of success with advantage are equal to ((the odds of success times (1 minus the odds of success) times two) plus (the odds of success squared)). Given that the odds of success are the same whether you manipulate the roll or the DC, the formula shows that advantage is not affected by this either.
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"these b...d brought a ladder, I did not think of that, it's too easy for them, therefore the wall is going to be harder to get over because otherwise it's a cakewalk, etc."
Bot that's my point: Bringing a ladder, the actions of the PC, changes the task and, therefore, the difficulty. You should be changing the difficulty of getting over the wall: It's an almost certain success to get over a wall with a long enough ladder. Similarly, if you had set the DC of climbing over a wall using a ladder which is already there, but the PC decides not to use that ladder, it's a more difficult task. Using the same DC for both is ridiculous.
1) DMG p. 244, Tracking DCs: +5/day since the creature passed, -5 if it left a trail. Also p. 244, a creature’s attitude determines the DC for getting a reaction, and players can change that attitude over the course of a conversation “if the adventurers say or do the right thing”.
2) “made it simpler” is exactly the same as saying “lowered the difficulty class”
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"Why do you need to complicate things and change a DC for something that has become trivial."
Why do you need to complicate things and set a DC for something so trivial, or something they may never even do?
At the end of the day, these two approaches are mechanically identical until you consider advantage/disadvantage, which can be applied either way. There is no difference between deciding climbing a wall is DC 20, then giving them a +15 to their roll because they brought a ladder, and waiting to see how they plan to climb the wall and deciding it should be a DC 5. In that case, you have waited to see exactly what action they want to take (in this case, climb a wall by hand or place a ladder against it and climb that) before deciding whether it has a chance of failure and, therefore, calling for an ability check.
Taking this even further: You know there is a wall for them to get past, and have decided in advance that it is a DC 15 to get to the other side. They then talk to a local band of mercenaries and have them use a catapult to knock the wall down. When you get there... You've already fixed the DC at 15 to get to the other side of the wall, so it's a DC 15 and always will be... even though the wall no longer stands and they can just walk across the rubble.
Once again, this is not about the quality of roleplay or anything like that. This is deciding the difficulty of what the player chooses to do.
How is there a single DC for a task, regardless of how that task is performed? How is the DC for getting over a wall always X if I might fly over it without effort whatsoever, or climb over it with a bit of effort, or decide to demolish the wall with a lot of effort? Or maybe the better question is, why are you setting a DC for “getting over the wall” when in practice you’ll only use the DC for how the PCs choose to try and get over the wall?
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'(and this is in the PH contrary to "modifying a DC")'
This isn't modifying a DC, it is setting a DC. It's just that you want to set a DC in advance before the PC has decided what action they are going to take, whereas I want to see what the PC is going to do before I call for the check, decide how difficult that course of action will be and set the DC.
1) Yes, but it shows that the DMG specifically suggests changing the DC based on circumstances. You claimed 5E never does that.
2) So DCs can be changed, and the official 5E ruleset explains this. That’s the point. Whether it does so retroactively or not isn’t pertinent to whether it does in the first place.
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Setting the DC is DM dependent RAW. Period. You can change it at will if you want and there is nothing wrong with that.
Not opinion as its written as such in the book. You can choose to do whatever with it but please do not shame people for following the book.
"Please re-read this post."
I have. If the only mechanic to be used is advantage/disadvantage, then you get ridiculous state whereby you have a 1 in 3 chance of not being able to climb to the top of a ladder. If you use absolute modifiers, too, then there is no mechanical difference between that and modifying the DC based on actions.
Please note, for me, the DC is set, not modified, at the time a player wishes to do something. You are just setting that DC earlier, before the player has finished telling you what they want to do.
"Again, see how absurd you have to make the examples ?the DC 15 would be for the task "get over the wall". If there is no wall, why would there be a task ?"
The examples are "absurd" to illustrate the absurdity of setting a DC in advance without taking into account the circumstances. We can modify it slightly: what if the mercs had knocked most of the wall down, but there was still a knee-high wall to get over? Is that still a DC 15 to "get over the wall"? That's absurd!
"Do we agree that the difficulty will not be the same to the barbarian who has advantage on his athletics check and for the wizard who has not ?"
No, the difficulty of the task is the same, the barbarian is just better at it. That's modifying for the character's abilities, not their actions nor the circumstances surrounding the action.