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Cliff Sedge
2020-06-18, 09:33 PM
(This is an asking for a friend post - i.e. I'm trying to settle an argument.)

According to the D&D 3.5e DMG (page 30), if circumstances are such that the task being attempted would be more difficult for anyone to do, then raise the Difficulty Class (DC). If circumstances are such that the character's ability to succeed increases, then add a bonus to the die roll.

This makes sense to me.

I don't have a 5e or PF DMG, but their core rules (available at d20srd.org and elsewhere) don't imply anything different to the guidelines given for 3.5

This question is general to currently-popular systems of D&D, so just appealing to the 3.5 rule book is (apparently, to my "friend") not good enough.

How should these kinds of modifications be handled?
(RAW or RAI, but RAW would carry more rhetorical weight)


Examples:
Open Lock check - let's say the published (or DM's default decision) DC is 25. The DM doesn't tell the players what the DC is. Two characters want to attempt it.

One has a +4 bonus from skill ranks and ability score, so cannot possibly succeed even on a nat' 20. The other has a +7, so could succeed on a nat' 18 or higher. Should the DM just tell the player with the +4 bonus not to bother because it would be impossible or allow success on a nat' 20?

I don't think either. I would let both roll for it, even knowing that one can't succeed (there is no reasonable way for the player or the character to know it was impossible).

Example 2:
Same DC 25 lock. One PC has 1 skill rank, but a +4 from high DEX. The other PC has 4 skill ranks and no other modifier. Should the game master lower the DC for the PC with more skill ranks because it should be easier for a more-skilled person?

I say no. The DC is dependent on the quality of the lock, not the quality of the locksmith's skill, right?

Example 3:
A wizard and a barbarian walk into a ruined settlement. The settlement was the barbarian's home village.
There are two relevant skill checks to help further the story: Knowledge-Arcana on some strange-looking glyphs carved by some elemental monster, and Knowledge-History to understand the meaning of a hastily-carved totem left by the displaced barbarians.

"Friend" says the DC for the Arcana check should be lowered for the wizard, because the wizard is an expert on elementals; the barbarian either doesn't get to roll, because it is an impossible task, or the DC should be higher for the barbarian because of lack of training compared to the wizard.

I say that the DC is whatever the DC is, and the wizard gets modifiers to the roll based on skill ranks and INT, and - unless the barbarian has training in Arcana - doesn't get to roll, or at-best could make an untrained INT check if the DC was 10 or lower (the DC would not be 10 or lower for this kind of task, though).

Also, even if the highest number the wizard could get was a 25 from all relevant modifiers and the DC was set at 30, I would still allow the roll. It doesn't seem reasonable that the character or the player should know that the task is impossible.

"Friend" says that the DC should be high for the wizard's History check, but low for the barbarian because the barbarian grew up here.

Again, I say keep the DC at whatever it is (still 30, say), but grant the barbarian some huge bonus to the roll - or even let it be an automatic success.



Does my way of doing it (which is identical to the 3.5e rule book) make more sense?

Do the rule books of 5e or PF say that the game master is supposed to adjust the difficulty class of a challenge subjectively based on character's ability and experience?

JNAProductions
2020-06-18, 09:39 PM
Example One
Agreed. In 5E and 3.P, there are no rules for autosuccess on 20s for skill checks, nor autofailures on 1s.

Example Two
Also agreed. The total modifier is what matters-for 3.P, some skills are "Trained Only" so you cannot even attempt them without training, but once you have that, +1 Rank and +39 Stat is the same as +40 Ranks and +0 Stat.

Example Three
I'd make the DC the same for both PCs, but give the Barbarian who has familiarity a bonus to their check.

A General Note
Mathematically, there's literally no difference between adding X to a PC's roll or subtracting X from the DC.

The roll is:

1d20+PC's Modifier≥DC

If they have no modifier (to make the math easy) this is how it shakes out:

(1d20+X≥DC)=(1d20≥DC-X)

A More Important General Note
If you're DMing for people, the table having fun is, far and away, the most important aspect. So all the math nonsense aside, do what will lead to the best time for all involved!

That being said, you seem like you've a good DMing head on your shoulders, at least from these examples.

Cliff Sedge
2020-06-18, 09:59 PM
Thanks. I've been a DM for decades, so I'd like to think I knew what I was doing. I am not as familiar with 5e or PF, so I was wondering if they had different guidelines.



A General Note
Mathematically, there's literally no difference between adding X to a PC's roll or subtracting X from the DC.

I have also been teaching mathematics for over a decade, so I know all sorts of ways to simulate probability. Even though the chance to succeed wouldn't change either way, there are a lot of problems with consistency if the DC was modified according to a particular character's abilities or training.

For example, I consider armor class (AC) as just another DC. If two fighters are attacking one armored opponent, the opponent's armor doesn't get worse because one fighter is stronger or more skilled. The increased probability for the better fighter is already reflected in attack bonus, etc.

Also, what about the save DC for a wizard's cast spell? How could it make sense that the innate difficulty to resist or avoid a spell would change because the victim knew more about magic?

Ah well . . .



A More Important General Note
If you're DMing for people, the table having fun is, far and away, the most important aspect. So all the math nonsense aside, do what will lead to the best time for all involved!


My players probably wouldn't know any difference, but I would lose my mind from the incoherence if I tried it "Friend's" way.

And "Friend" definitely thought my fun was wrong - angrily telling me how wrong and stupid I was (despite me being able to cite rule book page numbers, and he only able to appeal to "common sense").

Tanarii
2020-06-18, 10:46 PM
5e doesn't have "trained only". If a PC can make a check without auto failure, they make it with their bonus regardless of if it comes from ability score or proficiency.

But certainly a PC should get a bonus or auto succeed if they have extra personal familiarity, or a penalty or automatically fail if they don't. Using class isn't necessarily the best way to judge that though. Every time this comes up for Wizard vs Barbariam Arcana checks I want to roll up Conan the Librarian. :)

Again in 5e, there is potentially a difference between changing the DC vs giving the character a penalty or bonus. Mainly because the bonus or penalty is usually advantage/disadvantage, or potentially affected by it. But nothing says that two characters have to face the same DC. It probably works best to generally fix DCs for the same task, and some people religiously swear by that. But it's not required.

Pelle
2020-06-19, 03:42 AM
5e has a different approach to when to call for rolls than 3.5. The GM judges if what the player characers are doing has a chance of failure, and only call for a roll if the outcome is uncertain. And then it's up to the GM to set the DC and consequencences of the task based on the method and intent of the pc. And there are few predetermined tasks with set DCs as in 3.5, the GM is supposed to make a ruling.

So for Example 3, it can go different ways depending on how the GM rules it.

You could define the task as remembering something from this particular village, and set the DC high and let both roll for that. The barbarian gets to roll with advantage for being local, and the wizard has a high modifier from his abilities/skills (and possibly rolling with advantage for not being familiar with the place?).

Or, you could let the barbarian roll for the task "remembering something from your own village" - low DC, and let the wizard roll for another task "remembering something from an insignificant place you haven't been to before" - high DC.

In both instances both characters get to take advantage of their strengths, and both approaches are fine with me. It doesn't matter that the probabilites aren't necessarily the same. Just define clearly what you are rolling for first, and then how to set DCs and giving adv/dis comes naturally.

Quertus
2020-06-19, 05:51 AM
Note: I don't know 5e.

"more difficult for anyone to do, then raise the Difficulty Class (DC)" - makes sense.

"general to currently-popular systems of D&D, so just appealing to the 3.5 rule book is (apparently, to my "friend") not good enough" - makes sense (albeit strange - only general to D&D, not to RPGs in general?)

Example 1: "Should the DM just tell the player with the +4 bonus not to bother because it would be impossible or allow success on a nat' 20? … I would let both roll for it, even knowing that one can't succeed (there is no reasonable way for the player or the character to know it was impossible)." - makes sense. Also, there's no reason for the GM to know the character's bonus is +4. The conversation should be "open lock, I got a <roll> X" or "open lock" "OK, it's DC Y".

Example 2: "Should the game master lower the DC for the PC with more skill ranks because it should be easier for a more-skilled person? I say no. The DC is dependent on the quality of the lock, not the quality of the locksmith's skill, right?" - completely unreasonable. You are 100% in the right here. At least, as far as D&D is concerned. However, it would be perfectly reasonable to create an RPG where, say "D&D math" or "balancing a checkbook" was an automatic success for a +1 Int nuclear physicist, but "roll (with penalty)" for a +4 Int gradeschooler. So your friend is not "pants on head" insane, just wrong.

Example 3a: "Knowledge-Arcana on some strange-looking glyphs carved by some elemental monster,"

Example 3a1: "the DC for the Arcana check should be lowered for the wizard, because the wizard is an expert on elementals;"

Example 3a2: "the wizard gets modifiers to the roll based on skill ranks and INT,"

You're both wrong.

In 3e, the DC is the DC. The wizard gets d20+ modifiers, where "modifiers" includes Int, ranks, and circumstance bonus for being "an expert on elementals", if that's true *relative to other Wizards with equal ranks*.

Example 3a3: ”the barbarian either doesn't get to roll, because it is an impossible task, or the DC should be higher for the barbarian because of lack of training compared to the wizard.” - wrong. Either doesn't get to roll, or same DC. A more nuanced "the Barbarian gets to roll, but can only learn 'DC 10' facts" is the best answer for 3e.

Example 3b: "The settlement was the barbarian's home village… Knowledge-History to understand the meaning of a hastily-carved totem left by the displaced barbarians"

Example 3b1: "Friend" says that the DC should be high for the wizard's History check, but low for the barbarian because the barbarian grew up here.

Example 3b2: Again, I say keep the DC at whatever it is (still 30, say), but grant the barbarian some huge bonus to the roll - or even let it be an automatic success.

You are correct.

-----

Here's a wrinkle, relevant to 3a: a character (and a player) may not know what information they have that is relevant / that should give them bonuses. While the Barbarian's player could say, "I grew up here" when asked to make *any* roll (and, for 3a, be told, "you don't remember seeing anything like this in the village before" - which could be hilarious if it's said after they roll a '1'). But the Wizard has no reason to point out "I'm an expert in elementals" when looking at the runes, and it may be giving the player(s) knowledge that they don't have if the GM says, "take a +X circumstance bonus to the roll" if the Wizard then fails the roll so badly that they don't even recognize that it's elemental handiwork.

So the mechanic of "secretly modifying the DC" is actually sound *if* they fess up to it every time, after each successful roll ("you got a +2 circumstance modifier for your years spent studying elementals, giving you an X+2, which tells you that…"), and at scenario wrap-up (ie, if they spill the beans on "that was an elemental you fought / that made those runes", that's a good time to point out the circumstance bonuses that they gave).

This allows them to build trust in their otherwise seemingly "shell game" tactics.

----- EDIT -----


Or, you could let the barbarian roll for the task "remembering something from your own village" - low DC, and let the wizard roll for another task "remembering something from an insignificant place you haven't been to before" - high DC.

I really like this.

MoiMagnus
2020-06-19, 05:55 AM
A DC doesn't exist. Like HP, it is a gamified approximation of reality, that encompass a lot of (sometimes contradictory) concepts.
The fact that D&D doesn't include by default "partial successes" or "partial failures" doesn't help for that.

There are different school of thinking for them I know of:
1) The DC represent all the informations the DM has about the lock, including all the "secret parameters". The bonuses to the test represent all the parameters the PCs have control over (time they take to pick the lock, ...).
2) The DC represent the task, as objectively as it is possible. Locks have DCs like monsters have AC. Walls have climbing DC. Similarly to how every object has HP, every object has a DC for its common related actions. The bonuses to the test represent all the circumstantial parameters of the test.
3) The DC represent how likely a random NPC in a similar circumstance would succeed at the task. The bonuses represent how much better the PCs are compared to a random NPC.

The 2 is a very 3.X approach, where everything has a precise description, you have tables for DCs for multiple standard actions. And the player have usually countless small bonuses from circumstances.

The 3 is I think the intended approach in 5e. The only DC table included is a table for "easy/normal/hard/...", and the DM is supposed to pick a one of those DCs (all multiple of 5).

NichG
2020-06-19, 06:16 AM
I guess there's two things here.

One is a matter where the mechanics are identical but it's just how those mechanics are being communicated/calculated - should I have AC and THAC0 that both go down but I know exactly what I have to roll, or should I roll and add against a fixed value, or ...?

For that matter, the thing to keep in mind is that the player's bonus on a roll is information that they explicitly know, whereas DCs are information which they (usually) might have to infer. So if you modify the roll you're saying 'I want you to be aware of this factor', and if you modify the DC you're saying 'this is something that isn't immediately obvious, and makes the meta-game problem of inferring difficulty in this case more difficult'.

The consequence of modifying the DC rather than the roll is, if that same action can be attempted again, the person doing so might infer what the DC was based on the one character's success/failure, and then use that to decide if they want to attempt the action. If the DC changes for them, then it simulates there being some hidden factor that causes that judgement to be faulty, which is a valid sort of circumstance that can arise. Whereas if it's the roll that changes, it means they should be able to correctly predict what the difficulty is of the thing they're attempting.

For example, if I had enemies with allies that could sling around buffs/debuffs, I would interpret things that penalize a PC's attack roll as being factors obvious to them as to why it was hard/why they failed, whereas things that improve an enemy's AC would be interpreted as things which maybe the enemy is aware of explicitly, but their attackers don't necessarily know why it was suddenly harder. There are situations where an enemy's AC towards one PC could be higher or lower - abilities that care about relative heights, stuff involving marked targets, etc. So I wouldn't rule that out entirely as never being meaningful to use.

The other issue is, what kind of factors are legitimate reasons for an ad-hoc adjustment to a given roll (either by adding bonuses/penalties to the roll, or changing the DC)?

Using someone's skill rank to justify changing the DC isn't without precedent (there are 'cannot be attempted untrained' and 'cannot get above 10 untrained' type skill mechanics), and so using rank to modify difficulty suggests that there is some aspect of the task which only explicit training can permit you to do - in that case, I'd read it as modelling a situation where things like being generally better aren't a replacement for specific knowledge that someone with 4 ranks would have learned but someone with 1 rank would not have. I don't think the particular example reads like that sort of case to me.

Also, there's a hazard in adjusting DCs based on skill ranks - you're double-counting. The roll is already easier because of skill rank giving a bonus, so adjusting the DC basically makes skill rank count twice. Again, there are situations where that might be a reasonable way to model some kind of effect (e.g. 'for being good at balance, your innate Dexterity is worth as much as training, but for picking a lock your own nimbleness can't substitute for knowing that a McGreggor Mark V has 7 tumblers and that the factory pattern correlates the 3rd and 5th tumbler') - so you're saying, ranks invested count more for this skill. But if you do it without explicitly intending to double-count, it's problematic.

In terms of things like 'this person is a wizard and works with elementals, so they should know more' there's also a risk of double-counting, but it may or may not apply depending on the comparison. For some characters, Knowledge(Arcana), Knowledge(Nature), Knowledge(Planes) or whatnot will be class skills, and for others they won't. So some characters are already paying two ranks per rank to be as good as another character at it. If you use a broad justification like 'this person is a wizard, therefore' then you're double counting the thing that class skills already model. If on the other hand it's something where you'd say 'these are two wizards, but wizard A is a conjurer who has spent the last 15 years travelling the four elemental cities and specializes in elementals, and wizard B is an angel summoner, so Wiz. A gets an ad hoc bonus on rolls to identify elementals and Wiz. B gets an ad hoc bonus on rolls to identify exemplars' then you aren't double counting.

Dimers
2020-06-19, 08:47 AM
I'm not thrilled with 5e's skill system, but its fans have pointed out something about how it's intended to work that has made my non-5e games better. Sometimes the DM should say that a PC can't roll without being trained, and sometimes the DM should say that the PC succeeds without rolling because they are trained.

It's not just skill training, though. Sometimes the circumstances will make a task impossible or automatic, rather than simply modifying the difficulty. Like, no matter how good your Diplomacy roll is, it's not going to convince a high priest to give up her religion or make the emperor open his treasury to you. And you're not going to have to roll to convince a starving kid to eat the food you're offering.

It saves time and hassle, and it works well if the group have at least a moderate level of trust and respect for each other.

Composer99
2020-06-19, 09:44 AM
(This is an asking for a friend post - i.e. I'm trying to settle an argument.)

According to the D&D 3.5e DMG (page 30), if circumstances are such that the task being attempted would be more difficult for anyone to do, then raise the Difficulty Class (DC). If circumstances are such that the character's ability to succeed increases, then add a bonus to the die roll.

This makes sense to me.

I don't have a 5e or PF DMG, but their core rules (available at d20srd.org and elsewhere) don't imply anything different to the guidelines given for 3.5

This question is general to currently-popular systems of D&D, so just appealing to the 3.5 rule book is (apparently, to my "friend") not good enough.

How should these kinds of modifications be handled?
(RAW or RAI, but RAW would carry more rhetorical weight)

[Examples snipped for later use]


Does my way of doing it (which is identical to the 3.5e rule book) make more sense?

Do the rule books of 5e or PF say that the game master is supposed to adjust the difficulty class of a challenge subjectively based on character's ability and experience?

The 5e rule book is silent on the matter of varying a DC based on the capabilities of the character attempting the undertaking for which they are making an ability check. I would take that to mean in that edition that it is up to the individual DM to decide. In turn, I would say that whether or not to do so depends on the circumstances.

In any event, the primary way for 5e to modify the difficulty of any undertaking is by granting advantage or imposing disadvantage, rather than changing the DC or bestowing circumstance modifiers to the die roll; these can be applied either for changes in the character's capabilities or for changes in the difficulty itself.

In any event, it is true that there are tasks that are easy enough for those with sufficient training (represented in 3.5 by possessing some minimum number of skill ranks and in 5e by possessing proficiency) that might be very challenging or even impossible for the unskilled or amateur. 3.5 has a simple way of representing such tasks - they require a minimum number of skill ranks in a pertinent skill - while 5e does not. (I have homebrewed a way to represent such tasks in 5e - see my signature for a link.) What's interesting is that with such mechanics you don't have to just keep scaling up DCs to represent increased difficulty.

The 3.5 Disable Device skill is a good example - it's "trained only". The DC 10 jam a lock action you can attempt with that skill is very simple for anyone with any amount of training in that skill, but just is beyond the capability of the untrained, at least as per 3.5 RAW.

Given that, I think either you or your "friend" could be correct, but it's down to the DM/GM on how certain tasks requiring skill checks will be adjudicated. On the whole, however, 3.5 RAW does not support your "friend".


Examples:
Open Lock check - let's say the published (or DM's default decision) DC is 25. The DM doesn't tell the players what the DC is. Two characters want to attempt it.

One has a +4 bonus from skill ranks and ability score, so cannot possibly succeed even on a nat' 20. The other has a +7, so could succeed on a nat' 18 or higher. Should the DM just tell the player with the +4 bonus not to bother because it would be impossible or allow success on a nat' 20?

I don't think either. I would let both roll for it, even knowing that one can't succeed (there is no reasonable way for the player or the character to know it was impossible).

I don't have a 3.5 rulebook to hand, but I do know 5e recommends not calling for a roll whenever a task is impossible. If running a 5e game I would describe the player with the inadequate die roll modifier taking a few pokes at the lock and realising it is beyond their skill to pick, without calling for a roll.

Depending on what the 3.5 guidelines for DMs state, when running a 3.5 game I would call for a roll if the rules explicitly say to do so; otherwise I would default to the above.

However, unless there is some way for the insufficiently skilled character to recognise the impossibility of the task, I do not see anything wrong with calling for a roll as such - I just wouldn't do so.


Example 2:
Same DC 25 lock. One PC has 1 skill rank, but a +4 from high DEX. The other PC has 4 skill ranks and no other modifier. Should the game master lower the DC for the PC with more skill ranks because it should be easier for a more-skilled person?

I say no. The DC is dependent on the quality of the lock, not the quality of the locksmith's skill, right?

RAW here does not support your "friend". A DC 25 lock is an "average" lock. Anyone with 1 or more ranks in Open Lock can attempt to open it, while anyone with no ranks in Open Lock can't. The character with 1 skill rank and a +4 Dex bonus has some training but an abundance of innate talent (hand-eye coordination and fine motor skills); the character with 4 skill ranks and a +0 Dex modifier has better training & experience, but merely average innate capability. Well and good.


Example 3:
A wizard and a barbarian walk into a ruined settlement. The settlement was the barbarian's home village.
There are two relevant skill checks to help further the story: Knowledge-Arcana on some strange-looking glyphs carved by some elemental monster, and Knowledge-History to understand the meaning of a hastily-carved totem left by the displaced barbarians.

"Friend" says the DC for the Arcana check should be lowered for the wizard, because the wizard is an expert on elementals; the barbarian either doesn't get to roll, because it is an impossible task, or the DC should be higher for the barbarian because of lack of training compared to the wizard.

I say that the DC is whatever the DC is, and the wizard gets modifiers to the roll based on skill ranks and INT, and - unless the barbarian has training in Arcana - doesn't get to roll, or at-best could make an untrained INT check if the DC was 10 or lower (the DC would not be 10 or lower for this kind of task, though).

Also, even if the highest number the wizard could get was a 25 from all relevant modifiers and the DC was set at 30, I would still allow the roll. It doesn't seem reasonable that the character or the player should know that the task is impossible.

"Friend" says that the DC should be high for the wizard's History check, but low for the barbarian because the barbarian grew up here.

Again, I say keep the DC at whatever it is (still 30, say), but grant the barbarian some huge bonus to the roll - or even let it be an automatic success.

Knowledge is "trained only", and has explicit ways of describing the DC by RAW:

DC of 10 (for really easy questions), 15 (for basic questions), or 20 to 30 (for really tough questions)

So, unless the barbarian already has Knowledge-Arcana, the task is already impossible for them. It doesn't matter what the DC is. The wizard is benefiting from their training by being able to make the check at all. If they have a specialised expertise with respect to elementals, that would be represented by a circumstance bonus to the skill check in 3.5. If despite that circumstance bonus they couldn't decipher the glyph (because the DC is higher than any number they could roll), so be it.

For the skill check to recognise the totem left by the villagers, I would say that the barbarian should just know what it means, without requiring a check at all, while anyone who hasn't grown up there would have to make a Knowledge-Local check. (I think Local is better than History.) If the DC is 30, the meaning of the totem just happens to be very obscure knowledge for outsiders. If the barbarian had to make a check, you would probably (a) have to rule that they are allowed to make the check untrained (unless they had training in Knowledge-Local) despite the DC and (b) give them a very large circumstance bonus to the check.

For this last case, however, your "friend" is not wrong - as others have already stated upthread, the knowledge in question could very well be common/very easy knowledge (DC 10) for the barbarian, because of their historical ties to the village, while simultaneously being difficult (DC 20+) for outsiders.

Zarrgon
2020-06-19, 06:47 PM
Most often I will just tell a player if something is impossible: but I don't have to do this much. My play style is Extreme enough that most players "get things".

Example: DM:The lock on the door is made of what looks like solid white bone with small drops of blood sweating off it. As your hand gets close you can feel the unnatural cold emanating from the lock and then with a slight crackle it sucks all the heat out of your hand and arm...and all the hair on your arm falls off, and you take one point of damage.

Player:"Um...nope, my Open Locks of +5 is not gonna open this lock, lets look for another way around."


Buried in the skill Section of 3.5E is the circumstance modifier to skill checks, and I have always used that....plus many other modifiers.

D&D has always had skill check modifiers, in things like adventures or modules: but they have never made it into the Core Rules. But it's the simple idea that an elf from the high forest gets a +2(or +4) on skill checks about the history of the high forest. Or a sailor might know about a sea monster.

I avoid the silly "character knows everything" that many interpret into the rules. Like the idea that a wizard went to school and now knows about ALL magic. Though I do keep track of what a character knows about, and do let characters learn about things during downtimes.

The end result is like:

Set DC plus circumstance modifiers for time, place, etc. and set skill plus circumstance modifiers for the character and then special modifiers.

ImNotTrevor
2020-06-19, 08:46 PM
To explain my positions on things:

On "Is a 20 an automatic success":
Literally, no.
Functionally, yes.

What does this mean?

Having players roll when they cannot conceivably make the DC is a waste of time. Your time, their time, everyone's time. People generally know when something is above their paygrade. I am a chunky, physically awkward 29 year old. I know how to look at a jump and go "nah, I can't make that." It's possible that I'm mistaken on occasion, but if something will just flat out never be accomplished by me... I generally am aware of it.

So for example 1:
You've got two people who pick locks on the same team. Already a weird situation, but let's go with it.

Mr. +4 steps up and says "I wanna pick this lock."
I know he can't. So because he can't, and I'm not interested in wasting his time, and I reasonably assume his character knows that Ms. +7 is better at it than he is and there isn't a toxic dynamic, I say:
"You start picking it, and as you feel around in there... this lock is very tricky. There is some stuff going on in there that you don't have experience with. Ms. +7 might be able to do it, though."
And if it's 5e, I'd tell him that if Ms +7 taks him through her process of unlocking it and is successful, he'll get advantage next time he picks a lock. (To represent him learning something this time.)

Example 2:
DC doesn't change.

Example 3:
If the barbarian literally cannot make the roll, I won't bother making him roll for no reason. Just... "Yeah, this is way outside of your knowledge base. Like, you've hung out with Wiz long enough to know it's magical, in some ways. Maybe a couple of individual symbols seem sensical in the same way a middle schooler would recognize some parts of the math used for theoretical physics equations, but would not have any idea what they are in sum total."
(Would I say all of that? Probably no. But the Barbarian even trying would be an obvious hail mary attempt so... no.)

Otherwise, the DC is what it is.

As far as "wizard can't succeed, either" I just tell him it's above his knowledge set. That he can recognize elements, and he has a very rough idea of what it might mean, but there are some crucial elements he doesn't understand. BUT, if I set the DC knowing what his max is and/or I don't want him to get this informaton at all.... why is it here? I can accomplish the same thing by having vague-info laden but achievable DCs. If I goofed and thought he COULD do it, I'd make it a matter of how long he's willing to study. I guess I'd say that the total time (in hours) he'd need to suss out the meaning would be 30- His Roll. So he COULD figure it out, but at a possibly steep cost. That way, the information locked behind this DC is attainable and, therefore, has a purpose.


Example 4b:
Remembering a fact about your hometown and remembering a fact about, let's say, Jakarta, are very different tasks UNLESS your hometown IS Jakarta. (In which case, wow! What a happenstance! Hello!)

So the Barbarian and the Wizard aren't even doing the same thing. So giving them the same DC would be inaccurate. The tasks are very different.

Depending on the obscurity of the hometown fact, I might not make the Barbarian roll. But assuming it is still obscure enough to merit a roll, I'd definitely not have the DC match the Wizard. They're doing two different things, as another poster very rightly pointed out.

Lvl 2 Expert
2020-06-20, 01:24 AM
The difference between example 2 and 3 is that the skill the discount would be based on is more specific in 3. In example 2 the lock picking skill of the character is already taken into account. He has four ranks in it. In example 3 the substantial knowledge of the wizard about elementals is not yet taken into account. A biochemist and a bird watcher both have knowledge (nature), and they both get the same roll for identifying wolf tracks or seeing what's wrong with a sick looking tree, but one of them would realistically have an easier time identifying great tits, brown boobies and bounty island shags than the other.

This is DM's discretion, not a hard rule, but what it does is reward writing a good background, make the world feel more real and encourage smart play. I think in general it's good to for instance give some sort of bonus for knowing a religious detail about the specific god the character serves as a paladin. Because they are more likely to know that. In 5e that would be advantage. The wizard is a specialist in elementals and this is a check on knowing things about elementals? Advantage. The thief has a background specifying his skill with very specifically this rare type of lock that would confuse most inexperienced lockpickers? Advantage. The wizard wants advantage on every single arcana roll? Nope. Same thing for the thief on all lockpicking. That's a base skill, that's what your skill ranks and ability scores are for.



I don't really care for the distinction between lowering the DC for the barbarian or giving them a bonus to the roll. It's the same thing. In 5e it would probably be advantage again, unless the DM figured that's not good enough for knowing something about the place you grew up in. Might as well make it an automatic pass in that case. The barbarian can just read the "totem language".

I love advantage, it's a DM's best friend.

jayem
2020-06-20, 04:33 AM
I don't really care for the distinction between lowering the DC for the barbarian or giving them a bonus to the roll.

In the abstract U

Cliff Sedge
2020-06-23, 04:49 PM
5e has a different approach to when to call for rolls than 3.5. The GM judges if what the player characters are doing has a chance of failure, and only call for a roll if the outcome is uncertain. And then it's up to the GM to set the DC and consequences of the task based on the method and intent of the pc.

That is not a different approach compared to 3.5. It is identical.

In nether case do the rules imply that each character making an attempt face a different DC.

Rare exceptions like DCs for diplomacy/persuasion are based on persuader-audience relationship. The bard trying to rally a squad of troops might face a higher DC if the troops happen to hate bards; and the soldier who has fought alongside these troops before might face a lower DC, because the audience has a friendlier attitude. (*)

I think, in 5e, this is better handled by imposing advantage or disadvantage instead of adjusting the DC.

That is at least an example based on 3.5 rules (PHB 3.5e, page 64): "3. Reduce the DC by 2 to represent circumstances that make the task easier, such as having a friendly audience or doing work that can be subpar.
4. Increase the DC by 2 to represent circumstances that make the task harder, such as having an uncooperative audience or doing work that must be flawless."

Is there anything in the 5e PHB or DMG that is equivalent to what follows on page 64 of the 3.5 PHB?

"Conditions that affect your character’s ability to perform the skill change the skill modifier. Conditions that modify how well the character has to perform the skill to succeed change the DC. A bonus to the skill modifier and a reduction in the check’s DC have the same result: They create a better chance of success. But they represent different circumstances, and sometimes that difference is
important."

Cliff Sedge
2020-06-23, 05:07 PM
I'll come back later with more detail and examples of what I mean by the following:

I'm not looking for much discussion on specific cases like trained vs. untrained or don't bother rolling if it would be an automatic success or failure.

My intent here is to know, according to 5e RAW, is the DM supposed to adjust the DC of a task based on the abilities of the character making the check.

My primary objection to that is the redundancy incurred because the abilities of the character are already taken into account in the form of ability score modifiers and proficiency bonuses.


The sort of thing I am arguing against is when a DM makes the following call:

"If you want to attempt X, you'll have to roll a Y check. Player A, this is a DEX-based check, and your character has a high dexterity and a proficiency bonus for this sort of thing, so the DC you have to beat is a 15.

Player B, your character doesn't have a proficiency bonus for this kind of task, and your DEX score isn't as high as player A, so if you want to try it, the DC to beat is 20."

Why isn't it obvious that having bonuses/penalties to the die roll AND making the DC lower/higher simultaneously is redundant?

Lvl 2 Expert
2020-06-23, 05:19 PM
Yes, in that example it's redundant, because as you said those factors are already being taken into account. But now say that the players are trying to decipher handwriting. The barbarian already has pretty bad stats for it but happens to be barely literate as well, so the barbarian gets disadvantage. The rogue in general is about as good at this stuff as the wizard, but unbeknownst to the group the handwriting in question is the rogue's mother's, so the rogue gets advantage for it looking awfully familiar. That's what the advantage system (5e) or modifications to DC or roll (3.x) are for. It's for representing factors not included in the standard calculations of skill use.

Edit: I realized I made this more confusing than strictly needed. To clarify: The rogue would still get advantage for it being his mother's handwriting if his stats were rubbish, and the barbarian would still be penalized for being barely litterate if they somehow had a stellar decipher script skill while still being explicitely barely literate.

Pelle
2020-06-24, 03:38 AM
That is not a different approach compared to 3.5. It is identical.


Not really. In 3.5, if a character wants to tie his shoelaces, that's a use Rope check, and depending on the rules for DCs, players taking 10 etc it might be an automatic success and you don't bother rolling, but it is still using the skill mechanics. In 5e, the GM is given the responsibilty to make a judgement of if this is neccessary to roll for at all, and if it is only then you engage the mechanics.



In nether case do the rules imply that each character making an attempt face a different DC.


Not for the same task at hand, no. Depends on what you define the task as, though. In 5e they don't come predefined and the GM has to make a ruling on what you are rolling for.



Is there anything in the 5e PHB or DMG that is equivalent to what follows on page 64 of the 3.5 PHB?

"Conditions that affect your character’s ability to perform the skill change the skill modifier. Conditions that modify how well the character has to perform the skill to succeed change the DC. A bonus to the skill modifier and a reduction in the check’s DC have the same result: They create a better chance of success. But they represent different circumstances, and sometimes that difference is
important."

In 5e, for a given task, the DC isn't based on if it is easy or hard for the character attempting to do it, it is based on what is difficult for a platonic ideal normal person. So if you take a commoner with +0 and you think they should have 50-50 odds, then the DC should be 11. If your pc is skilled they will have a higher modifier and chance of success, but the DC stays the same. If they have a circumstantial reason for why they are especially well positioned for the task, that is what advantage is for, as you said.

Segev
2020-06-24, 11:43 AM
In general, Cliff Sedge (I like your punny name, by the by), I and the rules agree with you: the DC is the DC, and you don't change it based on anything about the people attempting it.

3e had "The DM's Best Friend," the +2 circumstance bonus. It generally recommended that you give +2 circumstance bonuses (or penalties) to characters for anything that would make them more likely to succeed (or fail) based on unquantified things about their character or, well, circumstances. The barbarian who grew up in town gets at +2 (or more) bonus to recognizing something relevant to that town. Or he even automatically succeeds, if it's something you'd have to have grown up in a box to have missed about the town while growing up there.

5e recommends giving Advantage or Disadvantage instead of circumstance bonuses, in general, but also is much more strongly in favor of "auto success" or "auto failure" if something about the character and circumstances make it dramatically appropriate. The barbarian who grew up in town definitely knows what those symbols his townsfolk carved mean. The wizard who didn't can't recognize them because they're unique to this tribe (or maybe he can piece it together if the DM decides there's some underlying order to them that the wizard should potentially recognize associations of).

But the DC is the DC. Things that are specific to characters should grant bonuses or penalties to the roll. In 5e, that usually just means Advantage or Disadvantage, but bonuses or penalties can also be appropriate.

Tvtyrant
2020-06-24, 12:31 PM
Most often I will just tell a player if something is impossible: but I don't have to do this much. My play style is Extreme enough that most players "get things".

Example: DM:The lock on the door is made of what looks like solid white bone with small drops of blood sweating off it. As your hand gets close you can feel the unnatural cold emanating from the lock and then with a slight crackle it sucks all the heat out of your hand and arm...and all the hair on your arm falls off, and you take one point of damage.

Player:"Um...nope, my Open Locks of +5 is not gonna open this lock, lets look for another way around."


Buried in the skill Section of 3.5E is the circumstance modifier to skill checks, and I have always used that....plus many other modifiers.

D&D has always had skill check modifiers, in things like adventures or modules: but they have never made it into the Core Rules. But it's the simple idea that an elf from the high forest gets a +2(or +4) on skill checks about the history of the high forest. Or a sailor might know about a sea monster.

I avoid the silly "character knows everything" that many interpret into the rules. Like the idea that a wizard went to school and now knows about ALL magic. Though I do keep track of what a character knows about, and do let characters learn about things during downtimes.

The end result is like:

Set DC plus circumstance modifiers for time, place, etc. and set skill plus circumstance modifiers for the character and then special modifiers.
Sounds like my Necromancer just found a super sweet doorknob of zombie healing tbh.