Why didn’t you know he was there? You’re aware of your surroundings and alert for danger during combat, so you’d have seen him go behind the pillar and not come out from behind it. You know where he is, you just don’t see him, which makes defending against attacks from him difficult because you can’t see his telegraphs. Again, this is someone anyone who has played a first person shooter has experienced, and probably used to their advantage.
My example was from an ambush, you did not know he was there because the rogue positioned himself behind cover before the start of the combat. So the first thing that you know of the rogue is when, out of nowhere, a crossbow bolt comes at you. Obviously, in that case, the rogue has advantage.
My point is that, after that, once the enemy knows that there is a rogue around, he will be more alert. And just because the rogue is skilled and clever does not mean that the adversary is not, that's all where my point about "dumb" monsters come about.
What I’m objecting to at this point is not your ruling, but your insistence that the alternative doesn’t make a bit of narrative sense. It makes plenty of sense if you have a different set of assumptions, as I explained above.
It might make sense to you, but still absolutely not to me. You claim that the rogue can choose if he attacks left or right, high or low, but it changes nothing to the fact that the adversary is aware of his presence, knows exactly where he is, that the rogue needs to pop out before he attacks and that the conditions are therefore not as good as the ideal case above. Hence the use of circumstantial modifiers as above.
Now, on the contrary, if the rogue, behind the scenes, is clever about changing positions, he might go back up almost to the perfect edge above, therefore fewer or no circumstantial modifiers.
It’s very simple. If you don’t assume that being “hidden” from someone means they have no idea where they are, but merely that they can’t currently see or hear you, then creatures don’t have to be idiots to get hit with advantage multiple times by an enemy hiding in the same spot.
I don't want to make that assumption because it's not what the rules tell you, and I want to take into account the fact that the conditions are less perfect, not only because it seems logical in itself, because it models properly what happens not only in reality but in all the genre and fiction, but also because it encourages the players to be creative rather than insist slavishly "but the rules allow it" (and while that bit is true, the rules also allow the DM to apply any circumstantial modifier that he sees fit, so it's still 100% RAW).
No, it isn’t. Being hidden gives the attacker advantage on attack rolls and imposes disadvantage on attack rolls against them.
No, you are confusing being hidden and not being seen, the sentence in the PH is quite clear: "When a creature can't see you, you have advantage on attack rolls against it."
So, even if you are hidden at the start of your action, if you are seen when you prepare or even when making your attack, the sentence above is clear, you don't have advantage (in addition to probably not being hidden anymore).
Right, but to what end? It gives no defensive advantage since your opponents can just walk around your ally, see you there, and attack you. And given your ruling it seems to give no offensive advantage either since you’re seen when you peek out from behind your ally to attack. So, it seems there’s no point. You’re just using a bonus action and rolling a Dex check to accomplish nothing at all.
First, the creature might not be able or willing to move (OA, good positioning, blocked, etc.). Second, see the other exchange about firing through allies (although there is cover). Moreover, I'm certainly not forbidding that, just applying circumstantial modifiers if you start becoming too predictable in your moves, nothing more.
Sure, he can watch for the halfling exactly at the same place. Then the halfling can lean out from the other side. Or he can crouch and pop out at a lower angle. Or he can stay where he is and arc a shot over his ally’s head, or between their legs.
And he can do that also when the creature is not even aware of his presence. So why would he not get the maximum bonus in that case as the rules intended, but why would it not be simply more difficult to execute when the adversary knows he's here ? My answer is, it becomes more difficult to hide there, as is perfectly logical.
Nothing about it suggests you wouldn’t be able to do so.
Except the plain logic that even a 5 years old playing hide and seek can explain to you.
Yes, the DM could rule that way, and it would be consistent with RAW. It would also make Naturally Stealthy useless, which makes me suspect it is not consistent with RAI.
Not useless at all, see above, it's perfectly useful at least once, and probably much more than that. But it's also not something that you can pull off every single combat round of every fight, for both in game and out of game reasons (like it's really totally boring).
I agree with this assessment of how attacking whole obscured by darkness works. That’s not the use case under contention here,
And it's still relevant to explain the complete mechanism as well as the DM's part in adjudicating all these edge cases, but since you agree, it's fine.
Concealment isn’t a thing in 5e, it’s either cover or obscurement.
Which is why I used quotation marks to signify exactly this. sigh
That’s up to DM discretion.
Exactly like applying circumstantial modifiers to a rogue that is being so unimaginative that he grants advantage to his adversaries in knowing where he is, what he is going to do and how.
I can’t parse this. What are you saying?
What I was saying is that when I hear some contributors here say that, when in doubt, they strip all the fluff and come back to the RAW, what they are doing is not roleplaying or deciding something because of the way the game world should "work", they are simply applying rules and then find a "slapped-on" justification to explain why it should be logical.
What I do is completely the opposite, I think about what looks cool in the world, how I want the players to feel when their character does something cool (usually because it's clever or imaginative), how it fits with the story and the roleplay and THEN I find the rule that applies the best, if it exists, otherwise I make a ruling. But the good thing with 5e is that the rules are fuzzy enough that I really rarely have to create a new rule, it usually fits like a glove.