Hiding vs Perception nonsense

[Zorku]

but as they all have the same PPS, that 50% average is really going to be the same as a single roll

And even if you use active perception, the more you roll the more likely your result it to approach the that average.

Rather, the advantage of having a lot of sneaky bugs all watching for intruders, wouldn't be out little dice math "advantage" but rather rely on the fact that the party is not going to easily find cover that applies to all of those sentries. It's easy enough to hide behind a rock or a barrel and keep a handful of people all in one direction from seeing you, but there's no side of a barrel that you can stick to that will keep you unseen while in the middle of those people. If having lots of bugs should have made it hard to sneak through an area it would be because you weren't obscured relative to some of them, not because they're better at watching.

The moment you have no cover and are not obscured, is the moment that you're seen regardless of passive perception. You don't even count as attempting to hide anymore.

[Zippee]

And even if you use active perception, the more you roll the more likely your result it to approach the that average.

Except that you don't care about the average here - that one roll that is a Nat20 is the one that matters, the average is just an interesting statistic. The more rolls you make the more likely you will have a successful result.

Rather, the advantage of having a lot of sneaky bugs all watching for intruders, wouldn't be out little dice math "advantage" but rather rely on the fact that the party is not going to easily find cover that applies to all of those sentries. It's easy enough to hide behind a rock or a barrel and keep a handful of people all in one direction from seeing you, but there's no side of a barrel that you can stick to that will keep you unseen while in the middle of those people. If having lots of bugs should have made it hard to sneak through an area it would be because you weren't obscured relative to some of them, not because they're better at watching.

The moment you have no cover and are not obscured, is the moment that you're seen regardless of passive perception. You don't even count as attempting to hide anymore.

The moment you have no concealment, you have no ability to Hide (unless: invisibility) so yes I agree, lots of bugs can make obtaining the cover necessary for stealth unlikely. However I don't think the original preposition was walking through a bunch of insects, it was approaching a bunch of them, stealth possibility presumed.

In that situation I don't see why more bugs should equal a better PPS.

[Psikerlord]

I had one pointed out to me recently. When it's opposed but you want it to be completely secret. Passive vs passive doesn't really work very well.

Yes its totally broken. Passive doesnt actually fix anything, it just creates new problems. Dont know how it survived playttesting.

[Spiritchaser]

Humanoids or beasts, I don't see how a group gets advantage to PPS just for being a group.

Your insectoids are sitting around doing what? Whatever insectoids do I expect, eating, grooming, working for the hive mother, why does the presence of many of them make them more likely to detect the party?

Do you have the party roll individual stealth/perception or do you use the group check (50% success) - you could apply the same to your insectoids but as they all have the same PPS, that 50% average is really going to be the same as a single roll (near enough not to want me to make a dozen rolls anyway)

I guess I just don't understand why you think having lots of creatures makes a difference - their presence constitutes a DC to the players' stealth, regardless of their number. If they were actively perceiving would you roll for each and every one or just a single roll? Would you allow them to 'aid another' in that roll (I wouldn't typically allow that for perception, except where one person who has spotted a thing is pointing it out to another) but if you allow a group of 20, 20 rolls then the party is going to be spotted. . .

In this case the bugs were simply waiting and resting while it was too bright for them outside.

My concern is that per current process, there is no clear way that these bugs would have any bonus to edit: perception, except if I rule that they have an advantage.

The reason I have this concern is that in reality, each bug has a chance to notice something, and has it's own sight lines. The more independent observers you have, the greater the cumulative chance of detection. This is modelled with multiple active observers, but not with multiple passive observers, unless you go all the way to "advantage"

Mathematically I can see the argument for doing so, although as noted, I did not do so here.

I always have every party individual roll stealth. It reinforces the vulnerabilities of less stealthy members, and the realities that stealth is easiest in ones and twos. A scout is generally needed... as it should be, and moving the entire party past an observer can be a tense moment.

In a large group of active searchers, historically only a few would be actively searching in the region where the party was. Those creatures would get a roll, enforcing how multiple active searchers with multiple lines of sight are going to be harder to hide from.

I've never had to roll 20 times for 20 active observers searching for the party right where it was. The party has never put themselves in a position where that was possible.

I don't consider this to be a major issue, but it feels like it's missing something.

[Spiritchaser]

Except that you don't care about the average here - that one roll that is a Nat20 is the one that matters, the average is just an interesting statistic. The more rolls you make the more likely you will have a successful result.



The moment you have no concealment, you have no ability to Hide (unless: invisibility) so yes I agree, lots of bugs can make obtaining the cover necessary for stealth unlikely. However I don't think the original preposition was walking through a bunch of insects, it was approaching a bunch of them, stealth possibility presumed.

In that situation I don't see why more bugs should equal a better PPS.

You're correct, in all cases it was quite literally a bug hunt mission, and the party wanted every tactical advantage they could get. In all cases there was cover.

In some cases the bugs got the drop on the party (quite literally) sometimes the party got the drop on the bugs.

In terms of hiding from multiple foes being harder, this is one area where it's all up to DM judgement. I'd suggest that in most cases, sneaking up on a group (providing they are not distracting each other) is just plain harder. Partly they're looking from different points, so there will be fewer safe places. Partly it'll just be odds. With more eyes, there will be more attention on a given region per unit time.

Again in this case I did not add advantage, but I do feel there needed to be some bonus. Had I paused to consider longer I probably would have added something.

[Zippee]

You're correct, in all cases it was quite literally a bug hunt mission, and the party wanted every tactical advantage they could get. In all cases there was cover.

In some cases the bugs got the drop on the party (quite literally) sometimes the party got the drop on the bugs.

In terms of hiding from multiple foes being harder, this is one area where it's all up to DM judgement. I'd suggest that in most cases, sneaking up on a group (providing they are not distracting each other) is just plain harder. Partly they're looking from different points, so there will be fewer safe places. Partly it'll just be odds. With more eyes, there will be more attention on a given region per unit time.

Again in this case I did not add advantage, but I do feel there needed to be some bonus. Had I paused to consider longer I probably would have added something.

No worries I think we're at the point of mostly agreeing.

We're only quibbling about levels of DM fiat, and that's perfectly reasonable

My thing is that I just don't see how a group of passive observers doesn't distract itself - by definition they must be doing something else and numbers make noise which helps the stalkers' stealth.

You feel more is better and thus they should have a bonus, that's cool - if it were me, I'd make the stalkers re-roll if their success was marginal. Either they stealth by a good margin or they need to test again, less powerful than ADV/DIS but adds to tension and risk as you describe one of the insects turning their way, antenna twitching, etc.

[BeefGood]

Had I paused to consider longer I probably would have added something.

This is an important general point. You did not pause to consider longer. Instead, you kept the game moving. That's good!

[Zorku]

Except that you don't care about the average here - that one roll that is a Nat20 is the one that matters, the average is just an interesting statistic. The more rolls you make the more likely you will have a successful result.

If you're saying that skill checks crit then that's homebrew bucko.
If you're saying that just one person has to pass, then you've ignored the group check rules: "If at least half the group succeeds, the successful characters are able to guide their companions out of danger. Otherwise, the group stumbles into one of these hazards."

If they're a group then more people rolling at something can drag down that one guy that rolled a nat 20, and muddy the results. It's too many chefs working on one pot. If they're totally not a group, then they're not really allies that communicate with each other. If you think the bugs get all of the benefits and none of the drawbacks then sorry but the game developers did not have that in mind when they tried to create fair and balanced rules for this game.

The moment you have no concealment, you have no ability to Hide (unless: invisibility) so yes I agree, lots of bugs can make obtaining the cover necessary for stealth unlikely. However I don't think the original preposition was walking through a bunch of insects, it was approaching a bunch of them, stealth possibility presumed.

In that situation I don't see why more bugs should equal a better PPS.

I covered that. If you want to walk up to a cluster of enemies then you can reasonably find appropriate cover. If you want to walk through them then you can not. You've got to be at least lightly obscured no matter what the situation is if you want to remain hidden, except with that generous DM caveat of distracted enemies.

If there are a bunch of bugs clustered together they're not going to see you way better than just 2 bugs would, because you've got the same cover that applies to all of them. If you wanna walk through a bunch of bugs then they're absolutely going to see you any time that their senses are not otherwise impaired.

Yeah, nobody exactly described this distinction, but this is why you would expect it to be hard to sneak around a large group rather than a small one, in terms of what's seen. If you're crouched behind a barrels but the tip of your shoe is sticking out past it, but not in a way that one creature is going to definitely see that, then 20 creatures with basically the same line of sight to the barrel are also not going to see that. 20 creatures with very different lines of sight to the barrel are going to see more or less of you, and at some point one of them is going to have enough to put the whole picture together. This is precisely why lots of observers matter, or do not matter; and it's deterministic in exactly the way it should be.

The reason I have this concern is that in reality, each bug has a chance to notice something, and has it's own sight lines. The more independent observers you have, the greater the cumulative chance of detection. This is modelled with multiple active observers, but not with multiple passive observers, unless you go all the way to "advantage"

No, that's modeled by cover, and you don't need to roll dice for it.

[Tanarii]

My thing is that I just don't see how a group of passive observers doesn't distract itself - by definition they must be doing something else and numbers make noise which helps the stalkers' stealth.

Easy. Guards on guard duty. They are using Passive Perception as they keep a lookout (task done repeatedly, over several area in field of view, round by round). Assuming they aren't chatting to each other or falling asleep at the post or playing cards, and are actively scanning the area: they get to use Passive Perception without disadvantage for being distracted.

Another example of Passive Perception while not being distracted: The front rank of PCs searching for traps or other threats as they walk down a Dungeon passageway. They are looking for secret things (thus use Passive score), they are doing the same task repeatedly as they travel (thus use Passive score), and they are not distracted.

Remember, Passive Perception does not mean passive on the part of a creature. And a rolled ability check does not mean active on the part of the creature. The Passive in Passive checks refers to the player/DM not rolling the dice, not the creature's in-game actions. (<--edit: this is defined in the very first sentence of the section on Passive checks.)

[Zippee]

If you're saying that skill checks crit then that's homebrew bucko.
If you're saying that just one person has to pass, then you've ignored the group check rules: "If at least half the group succeeds, the successful characters are able to guide their companions out of danger. Otherwise, the group stumbles into one of these hazards.".

check what you wrote Bucko:

And even if you use active perception, the more you roll the more likely your result it to approach the that average.

The more you roll, means that you only need one high roll - the average is irrelevant. And a Nat20 is the highest you can roll, critical or auto-success is not implied. If you roll multiple times, then eventually you will succeed, it does not matter what the results of the failed rolls are once the success comes along

And if you'd read the rest of the comments, you'd know SC had said he doesn't use the group roll mechanic, nevertheless you were the one that raised the fallacy that the average of many rolls was somehow important.

If they're a group then more people rolling at something can drag down that one guy that rolled a nat 20, and muddy the results. It's too many chefs working on one pot. If they're totally not a group, then they're not really allies that communicate with each other. If you think the bugs get all of the benefits and none of the drawbacks then sorry but the game developers did not have that in mind when they tried to create fair and balanced rules for this game..

Eh? More people rolling again. If they're individual rolls then they don't muddy anything. If it's a group roll then the combination is a success or failure based on the majority result. In either case the average of the rolls is irrelevant. Is this what you meant by 'more rolls' the whole group rolling, rather than calling for multiple rolls sequentially? Even so the average is irrelevant, it's the majority of successes or fails that matter, it requires very loose language to consider that the average of the rolls.

But I'm the one saying large groups aren't better at spotting - they are precisely too many chefs. And they aren't rolling anything, their PPS is the DC for the party's stealth roll(s) - unless, you know, I don't know what you mean. . .

And I'm lost how you think I've suggested the bugs get benefits to anything...

I covered that. If you want to walk up to a cluster of enemies then you can reasonably find appropriate cover. If you want to walk through them then you can not. You've got to be at least lightly obscured no matter what the situation is if you want to remain hidden, except with that generous DM caveat of distracted enemies.

If there are a bunch of bugs clustered together they're not going to see you way better than just 2 bugs would, because you've got the same cover that applies to all of them. If you wanna walk through a bunch of bugs then they're absolutely going to see you any time that their senses are not otherwise impaired.

Yeah, nobody exactly described this distinction, but this is why you would expect it to be hard to sneak around a large group rather than a small one, in terms of what's seen. If you're crouched behind a barrels but the tip of your shoe is sticking out past it, but not in a way that one creature is going to definitely see that, then 20 creatures with basically the same line of sight to the barrel are also not going to see that. 20 creatures with very different lines of sight to the barrel are going to see more or less of you, and at some point one of them is going to have enough to put the whole picture together. This is precisely why lots of observers matter, or do not matter; and it's deterministic in exactly the way it should be.

The discussion isn't/wasn't about cover - that's agreed. It's about stealth rolls and PPS. Those underlined bits are the distinction - and no-one's disagreed it. The question raised was why doesn't a larger group get a PPS bonus. I don't think it should, SC thinks otherwise. That's cool it's part of DM fiat but it's a decision made after the determination of whether there is cover or not. Cause, no cover: no hide thus no stealth roll(s).

[Zippee]

Easy. Guards on guard duty. They are using Passive Perception as they keep a lookout (task done repeatedly, over several area in field of view, round by round). Assuming they aren't chatting to each other or falling asleep at the post or playing cards, and are actively scanning the area: they get to use Passive Perception without disadvantage for being distracted.

Sure but a pair of guards dedicated to a task and a group of creatures in a cave / domestic situation are quite different. And I'm not suggesting they get DIS, I'm suggesting they don't get ADV. Pairs of guards are good because they can make it harder to hide by cutting down angles but they're not intrinsically better at PPS than a single guard.

The line you quoted was in the context of a large number of insectoids in a cave - I don't see how a large group like this is actually better than a single individual, someone on their own is likely to be more alert and doesn't have someone else scratching and coughing next to him; whilst groups tend to be doing other stuff and making noise and generally not paying attention outside of the group

Another example of Passive Perception while not being distracted: The front rank of PCs searching for traps or other threats as they walk down a Dungeon passageway. They are looking for secret things (thus use Passive score), they are doing the same task repeatedly as they travel (thus use Passive score), and they are not distracted.

Again, whilst I agree, I don't see how it relates to the situation under discussion. Although whether they are distracted is a moving target, once the wizard at the rear starts commenting on how the saddlebags on the pack donkey are empty, they'll get distracted right quick and then, you know: click, thunk, boom!

Remember, Passive Perception does not mean passive on the part of a creature. And a rolled ability check does not mean active on the part of the creature. The Passive in Passive checks refers to the player/DM not rolling the dice, not the creature's in-game actions. (<--edit: this is defined in the very first sentence of the section on Passive checks.)

And again how does this relate to the question?

As a reminder the question is whether a large group of creatures should have advantage on their PPS just because there are a large number of them?
.

[Tanarii]

Fair enough, context

I generally assume creatures in their 'home' environment, with no need to pay special attention, not on guard duty, not aware of possible intruders, are distracted by something. Or so absorbed in some task they don't get passive perception at all, of it requires focus the equivalent of Mapping, Tracking, Foraging, or Navigating (per the adventuring chapter). IMO that's reasonable.

[BurgerBeast]

The fundamental problem with many posters' views on this matter runs something like this:

(1) If you are capable only of hearing, you should have a chance to detect an enemy.
(2) If you are capable of hearing or seeing, your chances are generally better, and significantly better, to detect an enemy.

So, if the argument is that being unseen does not prevent one from being detected... that's fine.

But the argument is that if you are impossible to see, the chances of your being detected are the same as they would be if you could be seen... well... that's plainly B.S. no matter how many times you repeat it.

But the usual suspects will repeat this nonsense until they are blue in the face.

Also, sometimes you just don't see or hear someone. Insisting that this means one is therefore hiding is total B.S.

[Malifice]

The fundamental problem with many posters' views on this matter runs something like this:

(1) If you are capable only of hearing, you should have a chance to detect an enemy.
(2) If you are capable of hearing or seeing, your chances are generally better, and significantly better, to detect an enemy.

If youre only capable of hearing (are blinded) I can hide from you at will. In fact, each time I wander up to you, I cab [hide action] then move silently straight up to your face, and pull faces at you without you knowing I'm there.

This is impossible if you can see. Unless I'm invisible, or we are in darkness etc.

Also, if you cant see, you automatically fail perception checks that rely on sight alone. Spotting a far off bird and so forth.

So yes; creatures unable to see are at a marked disadvantage when it comes to noticing things.

[Spiritchaser]

The fundamental problem with many posters' views on this matter runs something like this:

(1) If you are capable only of hearing, you should have a chance to detect an enemy.
(2) If you are capable of hearing or seeing, your chances are generally better, and significantly better, to detect an enemy.

So, if the argument is that being unseen does not prevent one from being detected... that's fine.

But the argument is that if you are impossible to see, the chances of your being detected are the same as they would be if you could be seen... well... that's plainly B.S. no matter how many times you repeat it.

But the usual suspects will repeat this nonsense until they are blue in the face.

Also, sometimes you just don't see or hear someone. Insisting that this means one is therefore hiding is total B.S.

I’m going to hypothesize that some of the fear and or dislike for the idea of zero vision often offering advantage may be that invisibility would thus allow some casters to functionally match, or exceed the performance of expertise in stealth.

Others might be concerned about the power of expertise and invisibility on balance if it confers advantage.

Both would be valid play balance considerations, albeit not first order ones, and not ones I have personally found to be problematic.

[Easy_Lee]

I’m going to hypothesize that some of the fear and or dislike for the idea of zero vision often offering advantage may be that invisibility would thus allow some casters to functionally match, or exceed the performance of expertise in stealth.

Others might be concerned about the power of expertise and invisibility on balance if it confers advantage.

Both would be valid play balance considerations, albeit not first order ones, and not ones I have personally found to be problematic.

Invisibility shouldn't grant advantage on stealth. It should inflict disadvantage on perception checks to detect the invisible creature, same as obscurement does.

I'm trying to keep DMs honest. If you give your players disadvantage to detect hidden or obscured enemies, then you need to give enemies disadvantage to detect your invisible players.

If you don't give anyone disadvantage to detect an obscured creature, then what you're saying is that all perception checks rely purely on sound and sight has no impact. In that case, creatures hiding in the area of effect of the Silence spell ought to succeed automatically (meaning attempts to detect them automatically fail).

But if you say no, the creature would have to be invisible too, then you have a conundrum. What you're saying is that both sight and sound are equally effective at detecting a hiding enemy, and they neither rely on nor enhance one another. So if I'm blind or deaf, it does not affect my perception at all unless I'm both at once.

And that's ludicrous.

[Keltest]

Invisibility shouldn't grant advantage on stealth. It should inflict disadvantage on perception checks to detect the invisible creature, same as obscurement does.

I'm trying to keep DMs honest. If you give your players disadvantage to detect hidden or obscured enemies, then you need to give enemies disadvantage to detect your invisible players.

If you don't give anyone disadvantage to detect an obscured creature, then what you're saying is that all perception checks rely purely on sound and sight has no impact. In that case, creatures hiding in the area of effect of the Silence spell ought to succeed automatically (meaning attempts to detect them automatically fail).

But if you say no, the creature would have to be invisible too, then you have a conundrum. What you're saying is that both sight and sound are equally effective at detecting a hiding enemy, and they neither rely on nor enhance one another. So if I'm blind or deaf, it does not affect my perception at all unless I'm both at once.

And that's ludicrous.

Being invisible doesn't totally remove the sight component from searching though. You can't see the person, but you can still see all the signs of their passing, like footprints or disturbed plants.

[Easy_Lee]

Being invisible doesn't totally remove the sight component from searching though. You can't see the person, but you can still see all the signs of their passing, like footprints or disturbed plants.

That's wrong. Perception checks related to sight automatically fail if you can't see the target. A DM might count footprints or something, but that isn't in the rules.

Edit: strictly by RAW, footprints would let you know that a hidden target is present and allow active search checks. Normally, only passive checks are allowed - one more thing many DMs don't understand.

[Tanarii]

I'm just going to repost my post on how perception works in regards to the sight/sound separation question and advantage/disadvantage or automatic success/failure.

This was in the live thread that was the current thread, until someone pointlessly resurrected this one:
http://www.giantitp.com/forums/shows...5&postcount=13

"Exactly. Basically, you use the best of all senses available at any time. (For humanoids, smell is usually impossible or very hard, so it rarely comes into play. But animals it matters, they often get advantage.)

Automatic success = at least one sense will automatically detect them. The others don't matter.

advantage = at least sense will get advantage. None can be automatic success.

Normal = at least one sense is normal. None can be automatic success or advantage.

Disadvantage = at least once sense is at disadvantage. None can be automatic success, advantage, or normal.

Automatic failure = all senses automatically fail.

it is important to note, which sense is involved still matters. Because the outcomes and consequences, or what success looks like, is potentially different depending on if you see something, hear it, smell it. I mean, you detect something on a success. But exactly how/what is detected may change the way the player/PC responds to the situation."

[Spiritchaser]

But if you say no, the creature would have to be invisible too, then you have a conundrum. What you're saying is that both sight and sound are equally effective at detecting a hiding enemy, and they neither rely on nor enhance one another. So if I'm blind or deaf, it does not affect my perception at all unless I'm both at once.

And that's ludicrous.

I would not suggest this, in fact I’ve been suggesting quite the opposite since about page... 2 or so? Though I didn’t do it terribly effectively at first.

In any case I quite agree. For most normal observers most of the time, losing sight is generally enough to confer advantage on stealth/disadvantage on perception. The usual qualifiers for “normal” of course.


As for advantage or disadvantage?

Is it easier to hide because you don’t have to worry about cover or sight lines, or harder to find someone because they are invisible? The PHB only notes that if there is a special circumstance making things easier or harder, then that should be considered.

But there is another consideration:

I would note that if someone is searching for an invisible foe and you give them disadvantage, you have given part of the game away.

You’ve told them that there is a special circumstance making their job harder. If you give the invisible foe advantage you give much less away. Presumably they know they are invisible.

[Easy_Lee]

I would not suggest this, in fact I’ve been suggesting quite the opposite since about page... 2 or so? Though I didn’t do it terribly effectively at first.

In any case I quite agree. For most normal observers most of the time, losing sight is generally enough to confer advantage on stealth/disadvantage on perception. The usual qualifiers for “normal” of course.


As for advantage or disadvantage?

Is it easier to hide because you don’t have to worry about cover or sight lines, or harder to find someone because they are invisible? The PHB only notes that if there is a special circumstance making things easier or harder, then that should be considered.

But there is another consideration:

I would note that if someone is searching for an invisible foe and you give them disadvantage, you have given part of the game away.

You’ve told them that there is a special circumstance making their job harder. If you give the invisible foe advantage you give much less away. Presumably they know they are invisible.

I meant you in the general sense, not you specifically.

Many DMs keep track of players' passive perception scores. They also know creatures' passive perception. So unless someone is actively looking for someone, you don't have to give anything away. If the players deduce that a hidden creature is nearby, and the creature is invisible or obscured, then the DM would state disadvantage. I don't think that gives too much away.

[Spiritchaser]

I meant you in the general sense, not you specifically.

Many DMs keep track of players' passive perception scores. They also know creatures' passive perception. So unless someone is actively looking for someone, you don't have to give anything away. If the players deduce that a hidden creature is nearby, and the creature is invisible or obscured, then the DM would state disadvantage. I don't think that gives too much away.

I have had two trains pass in the dark before (low passive perceptions on both sides)

That said, one of the players took both the perceptive (UA) and the observant feats together, so that’s not really possible now.

If the players somehow know their foe is invisible, then no, it gives nothing away.

But asking a PC who is searching a pirate infested sea cave to roll at dissadvantage will tell them something.

[Cybren]

In D&D, no one really cares what direction you're facing, both in and out of combat. This is done to avoid needless, time-wasting distractions ("I move 30 feet, FACING WEST") and to never assume failure based on those directions ("you weren't looking behind you, you're surprised").

In any case, it's best to remember that the skill system is an abstraction, and not realism-driven.

I don't know where you get that your facing doesn't matter out of combat. That falls under the same thing as everything else: respect the fiction of the scene. If you said you're pouring over the map of the dungeon trying to find the secret exit, no, you aren't looking at the Dark Gazebo when it starts glowing

[Keltest]

That's wrong. Perception checks related to sight automatically fail if you can't see the target. A DM might count footprints or something, but that isn't in the rules.

Edit: strictly by RAW, footprints would let you know that a hidden target is present and allow active search checks. Normally, only passive checks are allowed - one more thing many DMs don't understand.

The description for invisibility and hiding specifically state that signs of an invisible creature's presence can still be noticed. That you cannot see the creature directly does not mean you cannot perceive it's presence visually.

[RSP]

Not to be "that guy" again, but, RAW, Invisibility doesn't grant Advantage to the stealthing, nor Disadvantage to the one perceiving, as it doesn't state this in the RAW.

Per the Advantage and Disadvantage section of the PHB:

"Sometimes a special ability or spell tells you that you have advantage or disadvantage on an ability check, a saving throw, or an attack roll...
...You usually gain advantage or disadvantage through the use of special abilities, actions, or spells. Inspiration can also give a character advantage (as explained in chapter 4, “Personality and Background”). The DM can also decide that circumstances influence a roll in one direction or the other and grant advantage or impose disadvantage as a result."

So to have Advantage or Disadvantage one of the following has to happen:

1) a special ability, action, or spell states Advantage/Disadvantage is imposed (not the case with Invisibility)

2) a character uses inspiration (not pertinent to this discussion

3) the DM determines circumstances deem Advantage and/or Disadvantage is appropriate

So yes, a DM can deem an Invisible character has Advantage or that those trying to find an invisible character have Disadvantage, but the Condition itself does not impose it because it would have to say it if it did (per the RAW).

[Spiritchaser]

Not to be "that guy" again, but, RAW, Invisibility doesn't grant Advantage to the stealthing, nor Disadvantage to the one perceiving, as it doesn't state this in the RAW.
.

Per RAW invisibility may grant advantage where appropriate, not where inappropriate as determined by the DM.

As before I would advocate that it usually should, particularly for humans who are very sight dependent.

Not, for example vs. A wolf, for which vision is a far smaller portion of its sum sensory ability

[Easy_Lee]

Not to be "that guy" again, but, RAW, Invisibility doesn't grant Advantage to the stealthing, nor Disadvantage to the one perceiving, as it doesn't state this in the RAW.

Per the Advantage and Disadvantage section of the PHB:

"Sometimes a special ability or spell tells you that you have advantage or disadvantage on an ability check, a saving throw, or an attack roll...
...You usually gain advantage or disadvantage through the use of special abilities, actions, or spells. Inspiration can also give a character advantage (as explained in chapter 4, “Personality and Background”). The DM can also decide that circumstances influence a roll in one direction or the other and grant advantage or impose disadvantage as a result."

So to have Advantage or Disadvantage one of the following has to happen:

1) a special ability, action, or spell states Advantage/Disadvantage is imposed (not the case with Invisibility)

2) a character uses inspiration (not pertinent to this discussion

3) the DM determines circumstances deem Advantage and/or Disadvantage is appropriate

So yes, a DM can deem an Invisible character has Advantage or that those trying to find an invisible character have Disadvantage, but the Condition itself does not impose it because it would have to say it if it did (per the RAW).

Is an invisible character obscured? If the answer is yes, then being invisible does result in disadvantage on perception checks to detect the character, in addition to automatic failure for checks that require sight.

If an invisible character is not obscured, then you had better have a damn good explanation as to exactly what the hell you think "obscured" means.

The rules aren't complex, they just aren't all in the same place. That's why DMs are supposed to be familiar with the whole book.

[Spiritchaser]

Is an invisible character obscured? If the answer is yes, then being invisible does result in disadvantage on perception checks to detect the character, in addition to automatic failure for checks that rely on sight.

If an invisible character is not obscured, then you had better have a damn good explanation as to exactly what the hell you think "obscured" means.

I think that the subtilty here is that most perception checks will depend, to various degrees, on multiple senses.

[Tanarii]

Is an invisible character obscured? If the answer is yes, then being invisible does result in disadvantage on perception checks to detect the character, in addition to automatic failure for checks that rely on sight.

They'd also need to have disadvantage to checks that rely on hearing.

Disadvantage only applies to checks that rely on sight (edit: for dim light or obscured). if you're using other senses without penalty, then there's no disadvantage to the roll. All senses need disadvantage for disadvantage to apply. All senses need to completely fail for automatic failure to apply.

If you can't hear or see someone clearly (and like most humanoids, have no chance of smelling them), THEN disadvantage should apply. If you can't hear or see or smell or feel or otherwise detect someone, then you should automatically fail.

If you bump into someone (touch sense automatic success) it doesn't matter if you can't see them due to invisibility, can't smell them due to a cold, can't hear them over the racket of the forge hammers ... you still detect them.

[Easy_Lee]

I think that the subtilty here is that most perception checks will depend, to various degrees, on multiple senses.

Subtlety, and we've been over that multiple times in multiple threads. If detecting a hiding target relies on both sight and sound, then the absence of one should affect the check - as it sure enough does according to dim lighting. If it only relies on sound, then the spell Silence results in guaranteed success for stealth checks. If it relies only on sight, then Invisibility results in guaranteed success.

The case I've seen is for DMs to give players disadvantage when the player is looking for an invisible or hidden creature, but conveniently forget about it when the player is trying to be sneaky. Such DMing is indefensible.

If your the type of DM to say "they're listening for you, no penalty" when the character is invisible, "they're looking for you, no penalty" when the character is silent, and "they smell you, no penalty" when the character is both, then I hope I never meet you.

They'd also need to have disadvantage to checks that rely on hearing.

Disadvantage only applies to checks that rely on sight (edit: for dim light or obscured). if you're using other senses without penalty, then there's no disadvantage to the roll.

By your implied logic, a character wearing a blindfold is just as good at finding hiding creatures as one with sight. Dim light and obscurement will never have any effect on detecting hidden creatures since someone like you will ALWAYS assume there's another sense involved.

And that's RIDICULOUS.

Perception ALWAYS relies on sight for any creature that has sight as its primary sense. Creatures that don't rely on sight have features like tremorsense and blindsight that specifically indicate that they don't "rely" on sight. Your interpretation means that these senses don't matter at all, because NPCs like dragons will only ever be looking for players in general play.