D&D 5E Perception and Readiness checks. Please Explain!!

[Sword of Spirit]

In general they've done a great job on the exploration rules. This particular packet actually cleared up some contradictions and ambiguities in regards to surprise.

However, problems still remain, as pointed out by the OP. I know I'll be bringing up every problem I can find in the feedback, because I'd like to see this sort of thing clearly defined in the rules. The basic problem I'm seeing is that there is no explanation of how to determine when an encounter starts where one group has the capacity to see the other group earlier than the other has the capacity to see them. Light sources and darkvision means this will come up all the time. It has to be clearly explained and defined by the book, from the very beginning.

 

[Mistwell]

. The basic problem I'm seeing is that there is no explanation of how to determine when an encounter starts where one group has the capacity to see the other group earlier than the other has the capacity to see them. Light sources and darkvision means this will come up all the time. It has to be clearly explained and defined by the book, from the very beginning.

I guess I am not understanding the confusion. Here are the two rules that cover this. How do they not address this issue?

1. "Surprise. If one group is hidden from the other, that group has surprise, as described in the combat rules. Otherwise, each creature and character makes a Wisdom saving throw against a DC that corresponds to its readiness. The readiness DC for characters is determined by their travel pace. For monsters, it depends on their degree of alertness, as shown below. "

2. "Encounter Distance. Typically, the terrain or layout of an area determines how far the characters are from creatures when the groups become aware of each other. If this distance isn’t predetermined, roll a d20 + 20. The resulting number is the distance in feet between the two groups at the start of their encounter. "

 

[Sword of Spirit]

Because it doesn't even begin to address visual and auditory range. Take these two scenarios.

1. A group of orcs is standing around in the dark in an enormous cavern debating the perpetual issue of whether hobgoblin or dwarf tastes worse. A party of torch-wielding adventurers traipses into the cavern at about 1500' distance. The orcs clearly see the adventurers' torches, because they are the only lights in a field of black. The orcs should be well aware of the adventurers before they get anywhere near them. They should have no chance of being surprised under normal conditions. And since they know exactly where the adventurers are, they can choose to initiate an encounter by making long ranged attacks at whatever distance they want. The adventurers won't even get a chance to make any checks unless they are close enough.

So, assuming the orcs decide to hide when they seed the torches, what determines when the adventurers are allowed to make Wisdom (Perception) checks? If they have to wait until they approach within 1d20 + 20 feet, (or even 1d20 + 20 x10 most of the time), the orcs can still choose exactly when the encounter begins by launching their attacks before then.

By the book, it would seem to require a 1d20 +20 x5 or x10 (depending on how the DM interprets the cavern's terrain) encounter distance roll...but the adventurers would be able to make Wisdom (Perception) checks at that time, and the orcs would still individually need to make readiness checks to avoid being surprised (unless one of them was keeping watch).

2. Same scenario as above, except that there are no lights. Orcs have 60' darkvision, adventurers don't. Everyone is out of sight, at least until 60', but nobody is hiding. Do we just roll the same encounter distance and then start? Do we drop the x10 modifier and just use the dungeons version since it's purely auditory--even though we aren't told to do that?

By the book, no Wisdom (Perception) checks are made or required (since no one is hiding--everyone is simply out of sight). You roll encounter distance, then everyone makes their check to see if they are surprised or not, then encounter begins. DM: "You see and hear nothing. I'll draw the location of orcs on your map. Roll initiative."

The point is that they need to include better rules for how sight, hearing (or other) senses on one or both sides interact with the otherwise excellent surprise and encounter rules. The concern I have is that they will under-address it if they read something like this, by simply saying, "If one side has the opportunity to sense the other side first, they can begin the encounter whenever they wish, and the other group is automatically surprised." They would create additional problems and still leave ambiguities if it were addressed that way, however. It needs some careful consideration.

 

[Klaus]

Because it doesn't even begin to address visual and auditory range. Take these two scenarios.

1. A group of orcs is standing around in the dark in an enormous cavern debating the perpetual issue of whether hobgoblin or dwarf tastes worse. A party of torch-wielding adventurers traipses into the cavern at about 1500' distance. The orcs clearly see the adventurers' torches, because they are the only lights in a field of black. The orcs should be well aware of the adventurers before they get anywhere near them. They should have no chance of being surprised under normal conditions. And since they know exactly where the adventurers are, they can choose to initiate an encounter by making long ranged attacks at whatever distance they want. The adventurers won't even get a chance to make any checks unless they are close enough.

So, assuming the orcs decide to hide when they seed the torches, what determines when the adventurers are allowed to make Wisdom (Perception) checks? If they have to wait until they approach within 1d20 + 20 feet, (or even 1d20 + 20 x10 most of the time), the orcs can still choose exactly when the encounter begins by launching their attacks before then.

By the book, it would seem to require a 1d20 +20 x5 or x10 (depending on how the DM interprets the cavern's terrain) encounter distance roll...but the adventurers would be able to make Wisdom (Perception) checks at that time, and the orcs would still individually need to make readiness checks to avoid being surprised (unless one of them was keeping watch).

2. Same scenario as above, except that there are no lights. Orcs have 60' darkvision, adventurers don't. Everyone is out of sight, at least until 60', but nobody is hiding. Do we just roll the same encounter distance and then start? Do we drop the x10 modifier and just use the dungeons version since it's purely auditory--even though we aren't told to do that?

By the book, no Wisdom (Perception) checks are made or required (since no one is hiding--everyone is simply out of sight). You roll encounter distance, then everyone makes their check to see if they are surprised or not, then encounter begins. DM: "You see and hear nothing. I'll draw the location of orcs on your map. Roll initiative."

The point is that they need to include better rules for how sight, hearing (or other) senses on one or both sides interact with the otherwise excellent surprise and encounter rules. The concern I have is that they will under-address it if they read something like this, by simply saying, "If one side has the opportunity to sense the other side first, they can begin the encounter whenever they wish, and the other group is automatically surprised." They would create additional problems and still leave ambiguities if it were addressed that way, however. It needs some careful consideration.

These things are so situational, no hard-and-fast rule will be able to cover them appropriately.

In your examples:

1 - The orcs are immune to surprise, because of the party's light source. They are hiding and keeping quiet, so the PCs can make Perception checks when they're within sight and earshot of the orcs (because the light from the torch might not illuminate the orcs, but it might reflect on a drawn weapon or on the orcs' eyes, or an orc might cough or something. In your example, I'd allow a check when the orcs are about to spring their attack. Those who fail are surprised.

2 - Since no one is hiding, you can determine that both groups become aware of each other, but aren't sure of the other group's location (Perception to pinpoint). At least until the groups are within 60' of each other, when the orcs can see the party. Here there's no surprise, but everyone is effectively invisible.

 

[Mistwell]

Because it doesn't even begin to address visual and auditory range. Take these two scenarios.

1. A group of orcs is standing around in the dark in an enormous cavern debating the perpetual issue of whether hobgoblin or dwarf tastes worse. A party of torch-wielding adventurers traipses into the cavern at about 1500' distance. The orcs clearly see the adventurers' torches, because they are the only lights in a field of black. The orcs should be well aware of the adventurers before they get anywhere near them. They should have no chance of being surprised under normal conditions. And since they know exactly where the adventurers are, they can choose to initiate an encounter by making long ranged attacks at whatever distance they want. The adventurers won't even get a chance to make any checks unless they are close enough.

Correct. This is covered by the rule, "Typically, the terrain or layout of an area determines how far the characters are from creatures when the groups become aware of each other."

Due to the terrain and layout, a 1500' cavern, the orcs become aware of the party when they enter. And due to the terrain and layout, the party would only have a chance to become aware of the orcs when they are much closer.

So, assuming the orcs decide to hide when they seed the torches, what determines when the adventurers are allowed to make Wisdom (Perception) checks?

Probably when the first party member gets stuck with an orcish arrow.

If they have to wait until they approach within 1d20 + 20 feet, (or even 1d20 + 20 x10 most of the time), the orcs can still choose exactly when the encounter begins by launching their attacks before then.

By the book, it would seem to require a 1d20 +20 x5 or x10 (depending on how the DM interprets the cavern's terrain) encounter distance roll...but the adventurers would be able to make Wisdom (Perception) checks at that time, and the orcs would still individually need to make readiness checks to avoid being surprised (unless one of them was keeping watch).

That's only the rule when the terrain or layout of an area fail to determine how far the characters are from creatures when the groups become aware of each other. In this case we know, it's 1500'.

2. Same scenario as above, except that there are no lights. Orcs have 60' darkvision, adventurers don't.

They adventurers are wandering blind? Okaaayyy....

Everyone is out of sight, at least until 60', but nobody is hiding. Do we just roll the same encounter distance and then start? Do we drop the x10 modifier and just use the dungeons version since it's purely auditory--even though we aren't told to do that?

Seems like 1d20 + 20 feet.

By the book, no Wisdom (Perception) checks are made or required (since no one is hiding--everyone is simply out of sight).

Hide is not dependent on intent, it's dependent on condition. Either cover, or concealment. In this case it's the later, as darkness is concealment.

"If one side has the opportunity to sense the other side first, they can begin the encounter whenever they wish, and the other group is automatically surprised." They would create additional problems and still leave ambiguities if it were addressed that way, however. It needs some careful consideration.

What additional problems?

 

[Baksartha]

It's a PLAYTEST.

Seriously, you need to be told a playtest of a game is for experienced players and DMs? It's not the whole book. They don't do the whole introduction to RPGs, to this game, to how to go about DM'ing, etc.. It's assumed you know all that, because you found your way there to the unadvertised sign-up only playtest sent just to members of Wizards.com with expressed prior interest in D&D.



First, the rules are not all there. Vast amounts of material are missing, particularly stuff that explains how to play the game if you're coming to D&D for the first time.

Second, I personally think that simplification is a huge strength of this version of the game. The level of complexity of the rules were, for me, getting in the way of the game. Put another way, the rules are not the game.

Never said I wasn't an experienced player. I've played from 1st edition to 3.5. I've also DM'd a fair amount of 1st and 2nd Edition d&d. I never played 4e.

In my opinion, with the exception of the "introduction to rpg's" you mentioned, I'd say the rules are largely all there. It's been my experience that the 'how to GM stuff really doesn't take up all that much room in any DMG I ever read, so, other than the omission of flavor text and artwork, I'm not exactly sure how you decided that "vast amounts" of rules are missing. It would be a crappy effort on Wizard's part if they didn't provide what we needed to accurately playtest the game.

Also, I fail to see how a simple clarification would overly complicate the rules. That just doesn't make sense. It has nothing to do with advice for new DM's, it has everything to do with making them game play smoothly. Nothing ruins the pace of the game more than a vague or confusing rule.

 

[Baksartha]

Looking at the rules, it's as if they don't want the encounter to start, in any fashion, unless it is within the confines of the encounter distance. So, if the party were traveling within a vast cavern, the DM would determine encounter distance, then both groups would roll Perception checks to detect creatures using stealth, then they would roll Readiness checks.

 

[bradzero]

I would say yes, unless one of the PCs decides he/she actually wants to actively search for something. I think the vagueness can be kinda fun to work with, because there is no right way to do it. It has everything to do with how you want to play and how your players are playing. Are they trying to sneak? Are they just walking and chatting, exploring what they think is an already cleared area? Unless the monster is a guaranteed TPK, let it get 'em, and then fight it out.

 

[Sword of Spirit]

Hide is not dependent on intent, it's dependent on condition. Either cover, or concealment. In this case it's the later, as darkness is concealment.

Nitpick: You have to take an action to hide, even if you are invisible.

Lots of stuff to think about. I don't agree 100% with the given interpretations, but I think I've identified the problem.

(Incidentally, I could have simplified the scenario by saying it's a wide open field, and one of the groups is invisible, but the cavern is more likely to come up.)

The way I would now interpret my own scenario is that the orcs will see the party from a long ways away and cannot be surprised. The orcs can therefore avoid the party, or attempt to move closer and ambush them. It appear that an encounter begins when both groups become aware of each other. As long as the adventurers do not become aware of the orcs before the orcs shoot crossbows at them, the orcs can choose when to begin the encounter. It would appear that when one of the orcs decides to fire, everyone (on both side) rolls initiative. This is important because a surprised character can take reactions after his first turn. This also means that orcs that don't have crossbows might have to pass on their actions (or ready an action to do something right after the orcs with the crossbows fire). The party members also make their individual Wisdom (Perception) checks to see which, if any, of the orcs they are now aware of, based on hearing.

The only real question regards when the party would have a pre-combat chance to detect invisible creatures. A crossbow has a long range of 400', and a short range of 100'. How close can the group get before checks are made based on hearing? It seems, following common sense, that the checks would begin at the same distance at which the adventurers would automatically detect the invisible group if they weren't sneaking. If this distance is too far is makes invisibility seriously weak. For instance, do you automatically hear an invisible creature walking 400' from you if it isn't trying to be quiet?

Which clarifies the real question: What is the distance for detecting other creatures based on hearing? If we know that, the rules appear sufficient to deal with the scenarios. Now, I'm not asking for precise rules. Just some sort of guidance so that DMs have a common frame of reference.

 

[Mistwell]

Nitpick: You have to take an action to hide, even if you are invisible.

You really think a paralyzed invisible creature isn't hidden, because it cannot take an action to hide? What action would that be, I 'think' quieter? Objects can be hidden, do they take a hide action as well?

I suppose a creature concealed in darkness can be heard, and therefore targeted with a ranged attack at disadvantage.