Perception checks

[Lauberfen]

I think I read some time ago on these boards someone complaining about traps (and hidden doors) being automatically spotted. I think the easiest way is simply to have the trap/secret door roll a stealth check (reduce the DC by 10 and add the roll a d20). The roll might account for the skill of the maker, or perhaps the door has become more visible over the years due to use, etc.

Exactly what I think- Certainly there should never be a perception 'check' made with no rolling on either side.

I just house rule that if neither side would ordinarily roll (such as trap vs passive perception), you make one side an active check instead. This works quite nicely, and eliminates the auto detect problem.

The real problem with passive perception is that active perception is not necessarily better, and is worse almost half the time. This means that unless you build a up a number of clues (as wizards intend), where passive perception picks up a clue, and further searching reveals the hidden door etc, you get into real trouble.

If you just have a secret door with no clues, you have a rather ridiculous situation where characters either spot it automatically, or are quite unlikely to find it when searching. This means that you have to choose for a party just to immediately know about the door with no effort, or accept that they probably won't find it even when they search.

This has really annoyed me as a player- I've taken a rogue through a dungeon, searching for hidden doors/traps as appropriate, fail to find them, and then trigger the trap. It makes searching seem pointless, as it mostly reveals nothing.

I personally am inclined to solve this by ruling that when searching (spending a minute per square), you add +5 to perception. This means that a door could be hidden to passive perception, but then would generally be found with searching.

 

[Nail]

This has really annoyed me as a player- I've taken a rogue through a dungeon, searching for hidden doors/traps as appropriate, fail to find them, and then trigger the trap. It makes searching seem pointless, as it mostly reveals nothing.

How does "rolling for it" change anything? You still have an average roll of ~10 (10.5), and so - on average - you find things just as if you used the Passive Perception check. No difference.

As I see it, the DM has 2 tools to make "finding stuff" (traps, hidden enemies, treaure, scret doors...) fun:

#1) Leave clues.

#2) Apply pressure.

Making the players roll dice doesn't add much.

 

[UngeheuerLich]

don´t forget to apply penalties for beeing far away (-2)... it could matter a lot!

 

[LostSoul]

I make most hidden stuff in my dungeons something that needs to be actively searched for. It takes 5 minutes or so to get a single roll; PCs can take 10 on this roll and they can Aid each other.

Since I use wandering monsters, and roll after each search attempt, this makes searching or not a meaningful choice.

 

[Neubert]

Traps are usually a lot more fun if the party both spot them and have to deal with them under pressure. A solo trap is a boring encounter that is resolved by one character rolling a few skill checks or attack rolls. Sure someone might lose a surge or two, but it's a bit dry.

Same trap in the middle of a fight is a lot different: you don't have the time to have people stand back.

I agree, traps should be used in relation to encounters in some way. However, my suggestion didn't imply either way, and also covered hidden doors, which can be used by itself.


Lauberfen - I have the same problem as you mention. I have considered to rule that your use your roll or passive perception (whichever is better) when you roll an active perception check, but it doesn't actually change anything as the passive perception would already have given a result for the character.

I also have a problem with giving out hints. Either they are too obvious, leading the players to "take 20" - or they are too subtle and are glossed over. Is there a middle way between these two?

I guess you shouldn't really do active perception rolls when searching, except in combat (when looking for stealthed monsters), or when you are under time pressure. It is only a minor action and as a minor action, I can see it being easy to miss important details (rolling lower than the passive perception). Instead you should take the time and do a proper search of the room instead of spending 6 seconds per 15 feet of floor/wall (making your standard and move action into minor actions for extra active perception checks).
Hmm, I just checked the book - it says if you are searching an area, it takes at least 1 minute to search each adjacent square.
I'm not sure where I am going with this.

 

[N0Man]

My thoughts on this are:

You can have DC can be to spot a clue in a high passive range, that might lead them to further searching of a higher DC. This is reasonable.

However, don't intentionally put all our DCs out of your entire parties passive range just to prevent an auto-success. You are cheating the players that may have made sacrifices in order to have a high perception.

Too many DMs worry so much about making sure that it's a challenge and that the players have to work for it always. They do things like boost the DCs so that their specialized party members will still have to be a little lucky, and the less specialized characters probably don't have much chance at all. If you are doing that then there's no point in the player even specializing, since if you going to just out of passive range anyway, they have the same chance without specializing.

In any kind of skill, the player who specializes should be rightfully rewarded, whether it's stealth, insight, perception, diplomacy, bluff, or whatever. Sure, you may know going in that they will automatically succeed, but you can also be pretty sure that one player is going to be pleased and saying, "man, I'm glad I picked up that skill focus feat".

The job of the DM is just as much to satisfy your players as it is to challenge them.

 

[AbdulAlhazred]

The DMG basically says to just assume that if the party thoroughly searches an area then you should assume they keep looking around until they get a 20 on a perception check. At that poing they are sure they have found anything they have any hope of finding.

Thus a party can take 10 and just be assumed to be wandering around in a fairly normal fashion, or they can search thoroughly and take 20. In between if they want to be moving with caution but not searching constantly then they will need to make active perception checks. Generally active checks WILL be a lot better than take 10 simply because you will have 5 die rolls. You can expect one of those to be well above 10.

As for secret doors I think the thing to do is look at the whole problem differently. In general if you want the party to find a secret door, then they should. If you don't want them to, then they shouldn't. Set DC accordingly.

If you want the door to be something they CAN find which will give them an advantage, then you probably want to do more than just put a door there with a DC on it. Maybe the party finds clues in different places. Maybe they can find clues by making perception checks to notice OTHER things, like tracks on the floor or even non perception checks that let them know something funny is going on. "Wait, how did that Orc get over there when we were blocking the way?"

The door itself can be impossible for them to perceive or else just difficult and in a spot they wouldn't likely search in the normal course of things. If they pick up the secondary clues, then they'll search and then the door will be found.

There just isn't really a whole lot of reason to have secret doors, traps, etc which the party finds by the luck of winning the dice roll lottery. Thus there really isn't a mechanism for that in the rules. That is there is a mechanism in that perception will tell you how to adjudicate it, but there is no standard automatic "maybe you found it" mechanism like the old "roll 2+ on a d6" kind of thing that was in 1e/2e.

4e assumes things are story driven and serve the plot of the adventure and that random happenings are not really a suitable mechanism for that.

 

[Lauberfen]

How does "rolling for it" change anything?

In just the same way that rolling to attack would be different from taking 10- if no rolls are made, then for a given DC of trap, the party have either 0% or 100% chance of spotting it passively. In effect, you decide whether they spot the trap or not.

I don't know about you, but to me it seems terribly wrong to place a trap knowing that the party will automatically notice it without trying, or that they have no chance of noticing it unless they search.

It also seems fundamentally wrong for a check to be made with no rolls at all.

 

[Neubert]

The DMG basically says to just assume that if the party thoroughly searches an area then you should assume they keep looking around until they get a 20 on a perception check.

My DMG-fu isn't that great - could you (or someone) give a pointer to where it says that?

 

[Nail]

It also seems fundamentally wrong for a check to be made with no rolls at all.

The check we're talking about has some fundamental differences from all other checks.

• In combat, if you miss (fail the check), you get to try again next round, and one missed check doesn't matter much over the course of an entire combat.

• For most skills (like diplomacy or athletics), a failed check gets you a poorer result than you'd like, but you still get a response, and the game continues along.

• For perception, a failed check to notice a secret door or hidden treasure gets you....nothing. Nothing at all. There's no "do over", and there's no way to react to "finding nothing' other than to move on.

In fact - as several people have pointed out - whether or not the secret widget comes into play in the adventure is entirely up to the DM. There is no real difference in rolling dice or using a passive (diceless) check. The PCs either find the secret, or they don't. Rolling dice is just a pacifier.