D&D General Perception vs Investigation

[TaranTheWanderer]

I was thinking the same for Perception for noticing the scrape marks on the floor where the bookcase looks like it swings open. So now the players know/think there is a secret door there and must roll an Investigation check to determine that you push a book, or there is a latch, or even just pull it and it opens. Would you just skip the second roll figuring that once they know where it is, they eventually will be able to open it? Give advantage since they know the exact spot to look? Just make the check Investigation to begin with?

Is there a difference with concealed doors and secret doors? I tend to make Perception to notice concealed doors behind a curtain or something. The two skills get blurry.

In my experience, the DM just says,

"You see a scrape on the floor where the bookcase swings. Pulling it open reveals a secret passage. "

Most DMs don't bother with two rolls. It's usually one roll to discover the secret door. And, to be fair, I understand why: why are you belabouring the process? They found the secret door - just reveal it already.

In my experience, the next step is that one of the players say, "I check for traps before opening the door"

And the DM checks passive perception or asks the player to make a roll and tells them whether there are traps. Play then moves on.

Edit: To clarify - it's not that I necessarily try to play things out this way when I'm DMing, I'm just saying that this is how the game plays out when I'm a player, regardless of the DM I'm playing with. Which is why I've changed it for my own games.

 

[DEFCON 1]

One other issue I have always had with using Investigation only for deducing things is that most of the time if there is something I want figured out, I want the players to be the ones to figure it out. That's the point of me putting in some mystery-type moment in the adventure in the first place. I am wanting to challenge the players and not just give another target number to roll against.

Now I don't have an issue with letting the players roll Investigation if they just aren't wanting to spend their time trying to figure the stuff out... but it does reduce the number of times Investigation would be rolled, and thus my desire to use it elsewhere as well. Using it to find traps and doors has been a lovely compromise.

 

[Stalker0]

In my experience, the DM just says,

"You see a scrape on the floor where the bookcase swings. Pulling it open reveals a secret passage. "

Most DMs don't bother with two rolls. It's usually one roll to discover the secret door. And, to be fair, I understand why: why are you belabouring the process? They found the secret door - just reveal it already.

I do agree with this point, I think in practice the notion of using two rolls to hammer out the scene just feels clunky, so I think the two skills often share significant overlap and it often boils down to which skill DM or player prefers.

The flavor text may differ between the two skills, but at the end of the day the result is the same.

That is not always the case, I do think there are things that are clearly perception or clearly investigation, but a lot of the "what do I find in this dungeon scene" example is often a place of heavy overlap.

 

[Sword of Spirit]

Some DMs treat Perception like 3.Xe’s Spot, and Investigation like 3.Xe’s Search. I don’t think this was the original design intent, but eh if people like using it that way and do so consistently, more power to them.

Actually it was originally that way in the play test. At some point (seems after the play test in my memory) they switched it mostly into Perception, which I feel makes what's already the best skill in the game ridiculous. Like others have described, I prefer Perception for creatures in Stealth or noticing non-hidden but easy to miss things, and Investigation for finding any hidden or secret non-creatures.

For a brief while (I think it was in an adventure anthology), that's how the official adventures did it too, before they gave up and just made everything Perception, thereby leaving Investigation about as useful as Handle Animal or Medicine.

 

[SkidAce]

I use Perception to see or notice.
Investigation to figure things out.

They can cross streams on occasion:

"I want to look for secret doors or that red book they were carrying"

"I want to study the area, I think there may be a secret door here. Oh and search the shelves for the most logical place for the book on magical traps"

 

[SkidAce]

I like having investigation be useful against traps specifically because rogues tend to have decent intelligence and often dump wisdom, so it improves their scouting ability. Plus, it then pairs well with sleight of hand to disarm the trap they found.

And there are some situations where I would rule that players can choose which to use, just as in some situations you might let players pick athletics or acrobatics. For example, maybe there's a secret door, and perception could let them notice something off in the environment that clues them in - a draught or something - while investigation might reveal the hidden mechanism, like the book that's really a lever.

But I don't think it matters too much how you rule, as long as you are consistent.

Better summary of my position.

 

[SkidAce]

Another example of the "same" difference.

Perception notices the tip of the bad guys boot sticking out from behind the curtains.

Investigation reveals that behind the curtains is the only place large enough for the bad guy to hide. (even if the boot wasnt visible)

I want keen eyed Legolas and Sherlock Holmes both to find/figure out things.

 

[Misanthrope Prime]

Perception is gathering sensory data, investigation is drawing conclusions from that data. Perception "happens" in the eyes, ears, nose, mouth and skin, "investigation" happens solely in the mind (I know, reductive).

 

[Charlaquin]

Actually it was originally that way in the play test. At some point (seems after the play test in my memory) they switched it mostly into Perception, which I feel makes what's already the best skill in the game ridiculous. Like others have described, I prefer Perception for creatures in Stealth or noticing non-hidden but easy to miss things, and Investigation for finding any hidden or secret non-creatures.

For a brief while (I think it was in an adventure anthology), that's how the official adventures did it too, before they gave up and just made everything Perception, thereby leaving Investigation about as useful as Handle Animal or Medicine.

It’s been a long time since the D&D Next Playtest, so my memory of it is not perfect, but I don’t remember this ever explicitly having been the case. I definitely remember a lot of folks on the WotC forums talking about using them that way in their playtests, and the developers saying that was a valid way to run it, but the emphasis at the time was very much on trying to encourage DMs to make the game their own, rather than trying to insure consistency across different tables. I mean, the earliest sage advice back then often gave contradictory answers, with Crawford giving the most direct RAW answer and Mearls describing a very different way he runs it, with the caveat that “Jeremy is the rules guy.” But from what I remember in the actual playtest packets, as soon as the skills list was solidified and Perception and Investigation were separate skills, they were described working as I said - with Perception being about what you can detect with your senses and Investigation being about what you can figure out with your brain.

 

[Charlaquin]

I like having investigation be useful against traps specifically because rogues tend to have decent intelligence and often dump wisdom, so it improves their scouting ability. Plus, it then pairs well with sleight of hand to disarm the trap they found.

Amusingly, I generally advise less experienced players that the PHB’s recommendation for creating a rogue is wrong, and that Wisdom should be a higher priority for them than Intelligence because Perception checks are so important for rogues to be able to find traps and secret doors. I tell them Intelligence can still be useful, especially for Arcane Tricksters, so don’t dump it, but that Wisdom should be at least as high as Intelligence if not higher. If you’re gonna dump anything, dump Strength.