Here’s the scenario. My players were navigating a maze of tunnels carved by a blue dragon and it’s minions. The tunnels were crystallized glass/sand and several pits were hidden beneath the floor. One of my players complained that I made them use investigation (rather than perception) to search for the pits as they moved; my reasoning was that perception would catch something out of place visually, but if the pits are perfectly camouflaged visually (since their covering was the same material as the rest of the floor) then they wouldn’t see anything without closer inspection (therefore, by investigating). What is your take on the situation?
For the record, the player complaining maxed his perception skill, not investigation, so they may have just been griping over not being able to use their “special skill” to avoid the trap.
I have this issue with my DMs sometimes. It can be frustrating to build a character to be really good at spotting something with perception, but every single looking around and searching check is investigation.
Investigation and perception sort of go hand in hand and it can be hard to tell where one ends and the other begins. To use an example, perception is noticing a seam in the brick pattern of a wall hiding a hidden door, investigation is figuring out how to open the seam to reveal the passage.
Or in this case, perception would be noticing discoloration or change in crystal arrangement that could indicate a thin spot or moved/replaced piece. Investigation reveals the trigger mechanism and function.
In general WIS is awareness/connection to the world and INT is the interpretation and understanding of information. You don't need to understand why this one spot in the middle of the walkway is different than the rest, but you do need to be aware that it is there to avoid it. And that is why trap and secret detection is perception, but finding/solving secret levers and mechanisms is investigation.
Other examples of what might be investigation include:
Searching a chest or cabinet for traps before opening (not in the open, much more about figuring out what would spring the trap than spotting it)
Searching for valuables (perception sees shiny things, investigation sees price tags)
Finding structural weaknesses
Locating strategically advantageous positions or safe hiding spots
Recognising that you have passed the same cactus or statue again. Not just a similar one, the same one.
At my table, it's simple. If you're looking for something you are not yet aware of, it's perception. If you're checking out something you are aware of, it's investigation.
In the most general terms, Perception is for broadly/narrowly scanning an environment based on your senses, and Investigation is for narrowly scanning an object/location and deducing information from it.
If a character is broadly scanning for things like traps/ambushes/secrets, a DM should have them roll (or use passive) Perception. If a character is narrowly searching something like a chest/desk/wall, for things that are "out of place"/"abnormal", Perception may still be the pertinent skill to roll. Depending on the nature of the things available for detection, and the method described by the character for their search (broad vs. narrow), a DM can adjust the DC accordingly.
Investigation is for deducing information from clues, not necessarily finding clues (in a vacuum). The skill description is not well-worded, but an investigation is usually done for things that you are at least partially already aware of. Searching a chest for traps may include a Perception check to notice that the chest isactually trapped, but deducing how to disarm it is an Investigation check. Reading someone's diary for information, such as the location of their hidden stash, is an Investigation check. Figuring out how to unlock a door is an Investigation check. Thoroughly searching someone's desk--such as pulling out and checking the back/underside of the drawers, feeling around for buttons/knobs/latches--for any clues that may be revealed (and what they may mean) is an Investigation check.
What it all boils down to is the question of, "Is this a thing that can reasonably be detected by a creature's senses?" Your player searching for environmental traps, regardless of their camouflage, is a Perception check. The fact that your traps are camouflaged very well should only affect the DC of that Perception Check.
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You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
I wanna dogpile on this and reiterate that seeing a trap, even a very well-disguised one, would be perception. Especially if it's a trap that the group has already encountered multiple times in the same dungeon. Figuring out how the trap works or how to disarm it would be an investigation check. Although keep in mind that if someone says, "I want to search for traps", you don't have to like... circle three spots on the game board and say, "Okay, there are pit traps here, here, and here". You can say, "there is a barely visible seam in the ground" or, "You notice a barely visible set of footprints that swerve to avoid a portion of the floor". Or even toss in a few false positives, like... "You notice a trio of holes in the wall", which are y'know... just left over from when someone had a picture frame bolted to the wall or something.
If the question is "do you see it at all", it's perception. If the question is "do you realize it's hazardous", that's investigation. In the case above, it would be perception to notice that there's something wrong about some parts of the floor, and then, if not obvious, investigation to know what.
In my games, anything involving noticing is perception. For simply noticing things, it's wisdom and perception, methodical searches are intelligence and perception. I use the investigation skill for interpretation/induction/etc. It's essentially the "give me a hint" button.
I would probably rule that carefully hidden traps roll perception at -5 (or whatever value I liked at that moment)
Never reduce or penalize a check when you can raise the DC instead. If you rolled a 19 and failed a DC15 check because the DM told you to subtract 5, that feels worse than rolling a 19 against a DC20 check.
And for that matter DC15 is already a moderately high check. I'd say this situation calls for around DC15-20 depending on how hidden they actually are (remember a DC20 is something a normal person could almost never accomplish).
A lower check can be used for investigation if you prefer.
The party was aware of the pits cause they rushed forward with no checks and fell in one....subsequently they started sweeping the ground with a quarter staff to find others...that’s when I started calling for investigation (DC 15). They just botched a lot of those rolls going forward
I would probably rule that carefully hidden traps roll perception at -5 (or whatever value I liked at that moment)
Never reduce or penalize a check when you can raise the DC instead. If you rolled a 19 and failed a DC15 check because the DM told you to subtract 5, that feels worse than rolling a 19 against a DC20 check.
And for that matter DC15 is already a moderately high check. I'd say this situation calls for around DC15-20 depending on how hidden they actually are (remember a DC20 is something a normal person could almost never accomplish).
A lower check can be used for investigation if you prefer.
We can't hammer this point home hard enough. When it comes to skill checks, always modify the DC of the check for circumstantial conditions. Remember that you do not have to disclose what the DC on the check is... just the outcome.
The party was aware of the pits cause they rushed forward with no checks and fell in one....subsequently they started sweeping the ground with a quarter staff to find others...that’s when I started calling for investigation (DC 15). They just botched a lot of those rolls going forward
Perception is definitely still the more appropriate skill check, and I would typically lower the DC a little bit as they are now aware that there are traps present. I would discourage Investigation here as it doesn't sound like they're trying to glean any information about the traps... it's literally just them relying on their senses to spot more of them. 100% Perception.
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
I would probably rule that carefully hidden traps roll perception at -5 (or whatever value I liked at that moment)
Never reduce or penalize a check when you can raise the DC instead. If you rolled a 19 and failed a DC15 check because the DM told you to subtract 5, that feels worse than rolling a 19 against a DC20 check.
I think this is a good DM table tip. It is mechanically identical and does not leave the player feeling cheated.
I would probably rule that carefully hidden traps roll perception at -5 (or whatever value I liked at that moment)
Never reduce or penalize a check when you can raise the DC instead. If you rolled a 19 and failed a DC15 check because the DM told you to subtract 5, that feels worse than rolling a 19 against a DC20 check.
And for that matter DC15 is already a moderately high check. I'd say this situation calls for around DC15-20 depending on how hidden they actually are (remember a DC20 is something a normal person could almost never accomplish).
A lower check can be used for investigation if you prefer.
We can't hammer this point home hard enough. When it comes to skill checks, always modify the DC of the check for circumstantial conditions. Remember that you do not have to disclose what the DC on the check is... just the outcome.
The party was aware of the pits cause they rushed forward with no checks and fell in one....subsequently they started sweeping the ground with a quarter staff to find others...that’s when I started calling for investigation (DC 15). They just botched a lot of those rolls going forward
Perception is definitely still the more appropriate skill check, and I would typically lower the DC a little bit as they are now aware that there are traps present. I would discourage Investigation here as it doesn't sound like they're trying to glean any information about the traps... it's literally just them relying on their senses to spot more of them. 100% Perception.
I think going forward I would agree. I had based it on the Blue Dragon sinkhole regional effect but then forgot to print it with the rest of my notes, so I improvised. That effect uses perception after re-looking at it just now so that’s what I’ll do in the future.
FWIW, their party has a high Perception PC and a high Investigation PC, but the High investigation guy is a lot squishier so they ran the other one at the front
Boy, you fellows can be pretty harsh. The mechanics are the same but you better not ever do it THAT way again!!! Really?
Well, it also doesn't make sense. A -5 to perception implies that there's something wrong with the player character. Like... it would be fair to create a temporary condition or environmental hazard that gives characters a -5 to all perception checks. But if checking for a specific well-hidden trap in the dungeon, giving the player a -5 to perception doesn't make sense, since that implies that there's something reducing their own ability to see the trap, when functionally the trap itself is simply hidden well enough that it requires a higher roll to perceive.
I don't think that it would be a problem per se to have a -5 modifier, it's just that it misses the point of the DC system.
This. It's just better practice because this system already exists, and it gives you (as the DM) more control over circumstances. If the mallus is from something directly interfering with the character's ability to use their skill (such as sand in the eyes), there's an existing answer for that as well--disadvantage.
We're intending to be constructive by passing along DM "best practice". Sorry if it's coming across negatively.
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You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
Just to support the above, the reason there's such a visceral reaction against the -5 malus is that it cuts against the very design philosophy of 5E. I recently started trying to pick up Fantasy Flight Games' Star Wars system, and by comparison it is very awkward to set the difficulty of things on the fly, because the DM has to start at a baseline difficulty of X number of Setback Dice (d6's), but then amplify the difficulty based on circumstances by either (A) adding additional setback dice or (B) enhancing some of those setback dice into difficulty dice (d8's) or (C) addiing additional difficulty dice or Challenge Dice (d12's). All of that not even to mention that the players themselves might be entitled to boost dice (different d6's) in addition to the ability dice (different d8's) and proficency dice (different d12's) that are on their character sheet, and.... it's a mess where at any given point nobody really seems to know how hard or easy anything is.
Yeah, it's a different game system, the details aren't important (they're far, far more complicated than even what's above)... but the point is, at the table when a DM has to make a decision on the fly, that system feels too arbitrary to be useful for them making snap decisions, and players experience analysis paralysis because whatever they do they are essentially rolling a contested check against an uncertain number of dice of uncertain types. 5E's system is elegant in its simplicity: the DM sets a base difficulty of a task (there's a helpful table to give you starting points), let the characters apply the bonus to their rolls that is printed on their character sheet, and then if circumstances make it easier give the players advantage, or if they make it harder give the players disadvantage. Once you know that a "hard task is DC 20" it's very simple by design... and starting to hand out static bonuses and penalties on the fly moves the goal post for players and DM too much, slows down play, and invites hurt feelings and controversy. Expect a real debate on every roll once your players know that landing a +X or avoiding a -X is always potentially on the table, including not only whether the bonus/penalty applies, but how much of a bonus it should be. Yuck!
1) If there is a reason why some task is more difficult than normal then the rules already provide two mechanisms for dealing with it
a) Higher DC for the task if it is difficult
b) Disadvantage on the skill roll reflecting some challenge to the character attempting the skill check
The DM doesn't need to apply some made up static circumstance modifier. Either set the DC appropriately or apply disadvantage.
2) To the OP ... in this case you need to decide if there is ANY way that a character can detect these traps.
a) If the characters have to notice the traps then it is a perception roll.
b) If the characters have to apply logic and deduce the presence of the trap based on some environmental effect that is easily noticed then it would be an investigation check. Investigation has to do with figuring out what things might mean. For example, searching a room and seeing some scuff marks on the floor or disturbed dust ... this is investigation to determine that a secret door might exist. However, noticing the hairline seam in the wall would be perception since once the seam is noticed it is obvious that there is a hidden door present though you may not know how to open it.
"but if the pits are perfectly camouflaged visually (since their covering was the same material as the rest of the floor) then they wouldn’t see anything without closer inspection"
Seeing something with closer inspection is STILL perception. The characters are spending more time and taking a closer look, noticing the signs of the trap, and then deciding what to do. If your traps were PERFECTLY hidden so that it was impossible to notice any visual difference in the floor then neither perception nor investigation would work. Perception doesn't reveal anything that can be sensed and without anything sensed there is nothing to investigate. One section of the floor looks the same as another. On the other hand, if the characters start hitting the floor with a staff then the floor over the trap might break or it might sound differently from an adjacent piece of flooring. If the difference in sound is small then you are still hearing a difference and it would be a perception check to see if the character noticed the difference in the sound. (Assuming that noticing the sound means that the characters realize a trap is likely present).
In some cases, characters will need to make a perception check to notice a clue AND an investigation check to figure out what the clue means assuming that they are doing the right things in the right area to figure out the problem. e.g. There are a couple of drops of dried wax under a desk, they are small and the character needs a perception check to notice them. It looks like they could have come from the desk. If the character investigates the outside of the desk they don't find anything however if they say they are opening the drawer nearest the wax drips and are investigating the desk/drawer then they can roll an investigation check to find the secret compartment (which contains a magical candle - thus wax).
At least that is how I tend to use perception and investigation - sensing vs thinking and logic.
Here’s the scenario. My players were navigating a maze of tunnels carved by a blue dragon and it’s minions. The tunnels were crystallized glass/sand and several pits were hidden beneath the floor. One of my players complained that I made them use investigation (rather than perception) to search for the pits as they moved; my reasoning was that perception would catch something out of place visually, but if the pits are perfectly camouflaged visually (since their covering was the same material as the rest of the floor) then they wouldn’t see anything without closer inspection (therefore, by investigating). What is your take on the situation?
For the record, the player complaining maxed his perception skill, not investigation, so they may have just been griping over not being able to use their “special skill” to avoid the trap.
I have this issue with my DMs sometimes. It can be frustrating to build a character to be really good at spotting something with perception, but every single looking around and searching check is investigation.
Investigation and perception sort of go hand in hand and it can be hard to tell where one ends and the other begins. To use an example, perception is noticing a seam in the brick pattern of a wall hiding a hidden door, investigation is figuring out how to open the seam to reveal the passage.
Or in this case, perception would be noticing discoloration or change in crystal arrangement that could indicate a thin spot or moved/replaced piece. Investigation reveals the trigger mechanism and function.
In general WIS is awareness/connection to the world and INT is the interpretation and understanding of information. You don't need to understand why this one spot in the middle of the walkway is different than the rest, but you do need to be aware that it is there to avoid it. And that is why trap and secret detection is perception, but finding/solving secret levers and mechanisms is investigation.
Other examples of what might be investigation include:
I think I've made the point.
At my table, it's simple. If you're looking for something you are not yet aware of, it's perception. If you're checking out something you are aware of, it's investigation.
"Not all those who wander are lost"
In the most general terms, Perception is for broadly/narrowly scanning an environment based on your senses, and Investigation is for narrowly scanning an object/location and deducing information from it.
If a character is broadly scanning for things like traps/ambushes/secrets, a DM should have them roll (or use passive) Perception. If a character is narrowly searching something like a chest/desk/wall, for things that are "out of place"/"abnormal", Perception may still be the pertinent skill to roll. Depending on the nature of the things available for detection, and the method described by the character for their search (broad vs. narrow), a DM can adjust the DC accordingly.
Investigation is for deducing information from clues, not necessarily finding clues (in a vacuum). The skill description is not well-worded, but an investigation is usually done for things that you are at least partially already aware of. Searching a chest for traps may include a Perception check to notice that the chest is actually trapped, but deducing how to disarm it is an Investigation check. Reading someone's diary for information, such as the location of their hidden stash, is an Investigation check. Figuring out how to unlock a door is an Investigation check. Thoroughly searching someone's desk--such as pulling out and checking the back/underside of the drawers, feeling around for buttons/knobs/latches--for any clues that may be revealed (and what they may mean) is an Investigation check.
What it all boils down to is the question of, "Is this a thing that can reasonably be detected by a creature's senses?" Your player searching for environmental traps, regardless of their camouflage, is a Perception check. The fact that your traps are camouflaged very well should only affect the DC of that Perception Check.
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
I wanna dogpile on this and reiterate that seeing a trap, even a very well-disguised one, would be perception. Especially if it's a trap that the group has already encountered multiple times in the same dungeon. Figuring out how the trap works or how to disarm it would be an investigation check. Although keep in mind that if someone says, "I want to search for traps", you don't have to like... circle three spots on the game board and say, "Okay, there are pit traps here, here, and here". You can say, "there is a barely visible seam in the ground" or, "You notice a barely visible set of footprints that swerve to avoid a portion of the floor". Or even toss in a few false positives, like... "You notice a trio of holes in the wall", which are y'know... just left over from when someone had a picture frame bolted to the wall or something.
Watch Crits for Breakfast, an adults-only RP-Heavy Roll20 Livestream at twitch.tv/afterdisbooty
And now you too can play with the amazing art and assets we use in Roll20 for our campaign at Hazel's Emporium
If the question is "do you see it at all", it's perception. If the question is "do you realize it's hazardous", that's investigation. In the case above, it would be perception to notice that there's something wrong about some parts of the floor, and then, if not obvious, investigation to know what.
In my games, anything involving noticing is perception. For simply noticing things, it's wisdom and perception, methodical searches are intelligence and perception. I use the investigation skill for interpretation/induction/etc. It's essentially the "give me a hint" button.
Never reduce or penalize a check when you can raise the DC instead. If you rolled a 19 and failed a DC15 check because the DM told you to subtract 5, that feels worse than rolling a 19 against a DC20 check.
And for that matter DC15 is already a moderately high check. I'd say this situation calls for around DC15-20 depending on how hidden they actually are (remember a DC20 is something a normal person could almost never accomplish).
A lower check can be used for investigation if you prefer.
The party was aware of the pits cause they rushed forward with no checks and fell in one....subsequently they started sweeping the ground with a quarter staff to find others...that’s when I started calling for investigation (DC 15). They just botched a lot of those rolls going forward
We can't hammer this point home hard enough. When it comes to skill checks, always modify the DC of the check for circumstantial conditions. Remember that you do not have to disclose what the DC on the check is... just the outcome.
Perception is definitely still the more appropriate skill check, and I would typically lower the DC a little bit as they are now aware that there are traps present. I would discourage Investigation here as it doesn't sound like they're trying to glean any information about the traps... it's literally just them relying on their senses to spot more of them. 100% Perception.
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
I think this is a good DM table tip. It is mechanically identical and does not leave the player feeling cheated.
"Not all those who wander are lost"
I think going forward I would agree. I had based it on the Blue Dragon sinkhole regional effect but then forgot to print it with the rest of my notes, so I improvised. That effect uses perception after re-looking at it just now so that’s what I’ll do in the future.
FWIW, their party has a high Perception PC and a high Investigation PC, but the High investigation guy is a lot squishier so they ran the other one at the front
Well, it also doesn't make sense. A -5 to perception implies that there's something wrong with the player character. Like... it would be fair to create a temporary condition or environmental hazard that gives characters a -5 to all perception checks. But if checking for a specific well-hidden trap in the dungeon, giving the player a -5 to perception doesn't make sense, since that implies that there's something reducing their own ability to see the trap, when functionally the trap itself is simply hidden well enough that it requires a higher roll to perceive.
Watch Crits for Breakfast, an adults-only RP-Heavy Roll20 Livestream at twitch.tv/afterdisbooty
And now you too can play with the amazing art and assets we use in Roll20 for our campaign at Hazel's Emporium
I don't think that it would be a problem per se to have a -5 modifier, it's just that it misses the point of the DC system.
I'm sorry if I came across that way--especially since my entire point was to not be harsh to the player :(
"Not all those who wander are lost"
This. It's just better practice because this system already exists, and it gives you (as the DM) more control over circumstances. If the mallus is from something directly interfering with the character's ability to use their skill (such as sand in the eyes), there's an existing answer for that as well--disadvantage.
We're intending to be constructive by passing along DM "best practice". Sorry if it's coming across negatively.
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
Just to support the above, the reason there's such a visceral reaction against the -5 malus is that it cuts against the very design philosophy of 5E. I recently started trying to pick up Fantasy Flight Games' Star Wars system, and by comparison it is very awkward to set the difficulty of things on the fly, because the DM has to start at a baseline difficulty of X number of Setback Dice (d6's), but then amplify the difficulty based on circumstances by either (A) adding additional setback dice or (B) enhancing some of those setback dice into difficulty dice (d8's) or (C) addiing additional difficulty dice or Challenge Dice (d12's). All of that not even to mention that the players themselves might be entitled to boost dice (different d6's) in addition to the ability dice (different d8's) and proficency dice (different d12's) that are on their character sheet, and.... it's a mess where at any given point nobody really seems to know how hard or easy anything is.
Yeah, it's a different game system, the details aren't important (they're far, far more complicated than even what's above)... but the point is, at the table when a DM has to make a decision on the fly, that system feels too arbitrary to be useful for them making snap decisions, and players experience analysis paralysis because whatever they do they are essentially rolling a contested check against an uncertain number of dice of uncertain types. 5E's system is elegant in its simplicity: the DM sets a base difficulty of a task (there's a helpful table to give you starting points), let the characters apply the bonus to their rolls that is printed on their character sheet, and then if circumstances make it easier give the players advantage, or if they make it harder give the players disadvantage. Once you know that a "hard task is DC 20" it's very simple by design... and starting to hand out static bonuses and penalties on the fly moves the goal post for players and DM too much, slows down play, and invites hurt feelings and controversy. Expect a real debate on every roll once your players know that landing a +X or avoiding a -X is always potentially on the table, including not only whether the bonus/penalty applies, but how much of a bonus it should be. Yuck!
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I'm going to make this way harder than it needs to be.
Two comments :)
1) If there is a reason why some task is more difficult than normal then the rules already provide two mechanisms for dealing with it
a) Higher DC for the task if it is difficult
b) Disadvantage on the skill roll reflecting some challenge to the character attempting the skill check
The DM doesn't need to apply some made up static circumstance modifier. Either set the DC appropriately or apply disadvantage.
2) To the OP ... in this case you need to decide if there is ANY way that a character can detect these traps.
a) If the characters have to notice the traps then it is a perception roll.
b) If the characters have to apply logic and deduce the presence of the trap based on some environmental effect that is easily noticed then it would be an investigation check. Investigation has to do with figuring out what things might mean. For example, searching a room and seeing some scuff marks on the floor or disturbed dust ... this is investigation to determine that a secret door might exist. However, noticing the hairline seam in the wall would be perception since once the seam is noticed it is obvious that there is a hidden door present though you may not know how to open it.
"but if the pits are perfectly camouflaged visually (since their covering was the same material as the rest of the floor) then they wouldn’t see anything without closer inspection"
Seeing something with closer inspection is STILL perception. The characters are spending more time and taking a closer look, noticing the signs of the trap, and then deciding what to do. If your traps were PERFECTLY hidden so that it was impossible to notice any visual difference in the floor then neither perception nor investigation would work. Perception doesn't reveal anything that can be sensed and without anything sensed there is nothing to investigate. One section of the floor looks the same as another. On the other hand, if the characters start hitting the floor with a staff then the floor over the trap might break or it might sound differently from an adjacent piece of flooring. If the difference in sound is small then you are still hearing a difference and it would be a perception check to see if the character noticed the difference in the sound. (Assuming that noticing the sound means that the characters realize a trap is likely present).
In some cases, characters will need to make a perception check to notice a clue AND an investigation check to figure out what the clue means assuming that they are doing the right things in the right area to figure out the problem. e.g. There are a couple of drops of dried wax under a desk, they are small and the character needs a perception check to notice them. It looks like they could have come from the desk. If the character investigates the outside of the desk they don't find anything however if they say they are opening the drawer nearest the wax drips and are investigating the desk/drawer then they can roll an investigation check to find the secret compartment (which contains a magical candle - thus wax).
At least that is how I tend to use perception and investigation - sensing vs thinking and logic.