D&D 5E Traps and DCs

[Psikerlord#]

Passive Perception is an excellent mechanic and solves the problem that many game systems have, namely, if everyone in the party always rolls, then nothing will ever be hidden, as with the dice variance, someone will roll high. The hobbits can't hide on the mountainside if 1000 passing orcs each get to roll to check to notice them. It solves a lot of problems.

You would just roll a group perception check for the orcs.

What problems does PP actually solve? If you look closely, you will find it only causes problems, imo.

 

[Ristamar]

There are no "odds" like you propose, unless there is a roll involved, and the end results are significantly different actually.

The DM knows the party's Perception scores, and if the trap DCs are static (e.g., the GM picks a pit trap or spear trap from the DMG), then the DM is basically just picking traps that either will be auto-found (boring/pointless) or auto-failed (annoying) by the PCs. And above I note the issues with an active Perception roll. Thus, instead, I suggest to make trap DCs based on a roll rather than static.

The significance of the difference is debatable, but I digress...

I agree that only using static trap DCs versus passive scores is a bad idea. We'll have to disagree that simply adding a thin layer of randomness via a single die roll by the DM makes a trap more palatable for the party.

 

[iserith]

But again, traps have static DCs, so if you are resolving with a passive Perception check, you have the issue of auto-fail and auto-find.

As for your comment about keeping eyes peeled, that was my point that characters would be doing that by default, so no need to get into reasonable specificity.

Then why are there static DCs listed in the DMG and adventures?

Ultimately sure if PCs are running, have bad light, etc., perhaps that warrants (a) disadvantage, (b) altering the DC, or (c) adjudicating auto-failure. (And vice versa, if they are in a treasure room and expect it to be trapped, and take extra caution and describe in particularity how they are exploring for traps, they might get advantage or alter the DC.) But there still needs to be a baseline DC to start with and work from.

Again, I suggest looking at it a different way. Traps don't have static DCs. A specific goal and approach to dealing with a trap has a DC. If the player articulates that specific goal and approach, then the listed DC applies. If some other goal and approach is articulated, another DC may apply (or outright success or failure). You're looking at what is effectively shorthand. When used in actual play, it must be taken into the context of the basic conversation of the game and the rules for ability checks.

See, your solution is to a problem of how you're looking at adjudication, not a problem with the game itself. Though I will say the game could be clearer on these points for sure.

With regard to the characters keeping their eyes peeled for hidden threats, while it's generally safe to assume competent adventurers are doing this, there is more to it. This choice comes with a trade-off. You basically can't do anything else at least as distracting as map-making, foraging, tracking, or navigating. Do any of those things or something similarly involved and you've got no chance of noticing hidden threats. Further, you must be in the fictional position to actually notice the trap e.g. the guy at the back of the party might not see a hidden threat at the front of the marching order. So I recommend getting some measure of specificity out of the players as they do things during play. Presuming character action without player input can lead to issues.

 

[slaughterj]

You would just roll a group perception check for the orcs.

What problems does PP actually solve? If you look closely, you will find it only causes problems, imo.

I'm not desirous of getting off-subject in this thread, so I'll just make the following comments about this subject. Rolling a group check *may* work for a group of Orcs spotting Hobbits, but it doesn't work well with a group of PCs with varying Perceptions getting ambushed by foes. I don't know how you would even roll, just one die for the whole party, and each apply a separate modifier? If you roll separately, nothing is hidden. Group check for the foes' stealth is necessary though (which is likely more uniform), else someone inevitably will roll low, and again, nothing would ever be hidden. But getting into groups makes it all more complex (more people maybe should spot foes more easily, but maybe they distract each other, and more people in an ambush group should be harder to hide, etc.), but passive Perception helps avoid the issue of too much rolling making hiding impossible.

 

[Wuzzard]

Iserith has the best approach. Now, getting your players to not always reach for the d20 and roll it before they even tell you what they are doing, that's complicated.

 

[slaughterj]

Again, I suggest looking at it a different way. Traps don't have static DCs. A specific goal and approach to dealing with a trap has a DC. If the player articulates that specific goal and approach, then the listed DC applies. If some other goal and approach is articulated, another DC may apply (or outright success or failure). You're looking at what is effectively shorthand. When used in actual play, it must be taken into the context of the basic conversation of the game and the rules for ability checks.

See, your solution is to a problem of how you're looking at adjudication, not a problem with the game itself. Though I will say the game could be clearer on these points for sure.

It appears that traps have a DC under the RAW, but setting that aside, I agree that the DC can and should vary based on PC actions. But even so, I would say that PCs should still have some chance to succeed or fail generally speaking (putting a shield in front of the poison needle trap and triggering it with mage hand might be an exception), and a roll should be involved usually. You might want it to be an active Perception roll against whatever the resulting DC is, and maybe that can work, though some may have high enough Perception to auto-succeed, and that may or may not be desirable. It may also not be desirable for PCs to auto-fail (say you have a low Perception party and the adventure has a high base DC for the trap and you are using passive Perception, and even with a careful approach, the DC still exceeds the party's Perception). I would prefer the party to have some chance of threat from even simple traps (else they become boring and pointless in event of auto-success), and a chance of success against traps that would otherwise be too hard (auto-fail sucks), so making the trap roll seems to work mechanically.

 

[iserith]

It appears that traps have a DC under the RAW

Sure, but my point is what the DC represents. You can't have a DC without the players first describing what they want to do otherwise you are putting mechanical process ahead of player input in contravention of the basic conversation of the game (Basic Rules, page 3). I submit that when you start thinking about things this way, it makes a whole lot more sense.

I agree that the DC can and should vary based on PC actions. But even so, I would say that PCs should still have some chance to succeed or fail generally speaking (putting a shield in front of the poison needle trap and triggering it with mage hand might be an exception), and a roll should be involved usually.

Only if what the PCs are doing has an uncertain outcome as established by the DM. Players seeking to succeed should naturally be striving to eliminate that uncertainty as best they can while pursuing the goals of play. If they aren't trying to do that or aren't very good at it, then yeah, you're right to expect more rolls.

Now, if you're a DM who subscribes to the "Roll With It" approach as outlined in the DMG (page 236), then more rolls are just part of that style. However, the DMG does suggest there can be a pretty significant drawback to playing this way - roleplaying diminishes as the players realize that dice, rather than their decisions and characterizations, always determine success.

You might want it to be an active Perception roll against whatever the resulting DC is, and maybe that can work, though some may have high enough Perception to auto-succeed, and that may or may not be desirable. It may also not be desirable for PCs to auto-fail (say you have a low Perception party and the adventure has a high base DC for the trap and you are using passive Perception, and even with a careful approach, the DC still exceeds the party's Perception). I would prefer the party to have some chance of threat from even simple traps (else they become boring and pointless in event of auto-success), and a chance of success against traps that would otherwise be too hard (auto-fail sucks), so making the trap roll seems to work mechanically.

I think the key thing I want to try and get across is that player input precedes and can regularly obviate an ability check. So setting a DC for a trap in a vacuum without tying it to a specific approach is saying that any approach to dealing with it has an uncertain outcome. This removes player decision-making from impacting the outcome with a possible drawback as noted by the DMG. It can also encourage players to pump their Perception as high as possible since they know their input isn't as important as their characters' stats.

 

[Rya.Reisender]

Don't you think a player's smarts should matter when it comes to playing a game?

Usually yes, but not when role-playing. Then it should matter how well you play your role.

 

[Rya.Reisender]

Active Perception takes an action though, unless you are dropping that requirement.

Also, asking the PC to make the Perception roll puts them on alert.

That's all well and good for interesting, involved traps, but many traps are just simple pit traps, poison needles in locks, darts/spears launched, etc., and warrant a simple mechanic to resolve. And the simple mechanic offered in 5e seems broken when it operates on an auto-find / auto-fail binary system based on static Perception vs static trap DC comparisons, so I am offering a simple alternative here that solves the aforementioned problems.

1. Outside combat there is really no need to track of actions (it's said that one round should be around 1 minute in dungeons, so that would allow room for 10 actions anyway).
2. Active checks are NOT always an action, it depends on the how long the action takes and that's for the DM to decide.
3. Let's say a player doesn't have enough passive perception to notice the trap, you are already at a point where the trap would activate if it's not noticed. Even if you then ask the player to do a perception check, it doesn't matter if it makes him alert, because on a failed roll the trap will already go off and he has to do a saving throw.
4. Even simple traps can be narrated in an interesting way. Even if getting caught by it or not is just binary, you can still make a memorable moment out of it simply by narration and with the helps of your player it can lead to funny dialogues. And as explained earlier what you criticize about 5e isn't actually how 5e is supposed to be played, it's just your misinterpretation of what passive perception means and what finding a trap means.

 

[wedgeski]

Sure, but my point is what the DC represents. You can't have a DC without the players first describing what they want to do otherwise you are putting mechanical process ahead of player input in contravention of the basic conversation of the game (Basic Rules, page 3). I submit that when you start thinking about things this way, it makes a whole lot more sense.

But what's your starting point? What differentiates a "good" trap (one that's difficult to find and good at its job) from a "bad" trap (botched, obvious, easy to avoid) if you build you DC's from player narrative?