I'm a bit confused about the chart on page 563 of the PRGCR regarding the Invisibility Special Ability in Appendix 1. The text states that "there are a number of modifiers that can be applied to this DC if the invisible creature is moving or engaged in a noisy activity." Then follows the chart, which appears to list modifiers to the Perception DC. Is this referring to the DC 20 to know when an invisible creature is within 30 ft., or the check to pinpoint the creature? The text also states that the DC is at +20 to pinpoint an invisible creature; is this referring to any of the normal DCs listed under the Perception skill or the DC 20 to know an invisible creature is present, or both?
The numbers in the chart don't make sense if they are modifiers to a DC... the modifier for someone not moving is -40!!
I think it is meant that way:
If you want to notice an invisible creature the DC is 20.
If you want to pinpoint it the DC is 40.
These two DCs are modified according to the table on page 563.
The numbers in the chart don't make sense if they are modifiers to a DC... the modifier for someone not moving is -40!!
That in fact is something I do not understand. I would guess that the "minus" is wrong, because the DC to pinpoint a creature is simply 40, not "minus 40".
Or you could just ignore that line because there is no information in it.
Well Zerberus beat me to the punch with a shorter post, but I'll paste this in anyway.
I believe the numbers in the chart are modifiers to the Perception DC; they make it easier or harder to notice or pinpoint invisible characters. So for example normally you can "notice the presence of an active invisible creature within 30 feet" with a DC 20 Perception check. Looking at the table, if the invisible creature is yelling or speaking at you the DC is 20 - 20, or 0, so you would almost automatically realize that an invisible creature was present. Realizing they're present doesn't help you pinpoint their location though; for that you normally need to beat a DC 20 + 20 = 40 Perception check. If the invisible creature is speaking that makes it easier to pinpoint their location: the DC for your Perception check is 40-20 = 20.
For matching things up with the Perception skill you may want to look at the spell invisibility, which says invisible creatures get a +40 bonus to their Stealth checks, or +20 if they're moving. So it could be that the base DC 20 Perception check to "notice the presence of an active invisible creature within 30 feet" is based on this; you assume the creature has a 0 check result and a +20 bonus? Or a +40 bonus if they're not moving, explaining that DC.
I think you found an important typo here: the line for "Not moving" should say +40 rather than -40. It could be someone was looking at the +40 for not moving in the invisibility spell and made a mistake when transcribing the table. But yes, I believe that if an invisible creature is not moving they should be very hard to notice or pinpoint: +40 to the DC to notice them (bringing it to DC 60) or DC 80 to pinpoint their square :P At that point you probably want to break out the glitterdust, a see invisibility spell, a dog with scent, or some other means of assistance.
Fixing the "not moving" table entry also makes things jive with the entry for "Using Stealth": if the invisible creature is moving the Perception DC is equal to their Stealth check +20, or Stealth check +40 if they're not moving.
This is a good catch; if it hasn't already been mentioned I will make a post in the errata thread.
The text also states that the DC is at +20 to pinpoint an invisible creature; is this referring to any of the normal DCs listed under the Perception skill or the DC 20 to know an invisible creature is present, or both?
I believe the act of pinpointing an invisible creature is a special action - you're trying to figure out exactly where they are (within a 5 ft space), usually so you can attack them, use spells, or do things of that nature. Thus, yes, if it's normally a DC 20 to notice an invisible creature it would be DC 20 + 20 = 40 to pinpoint their location.
the chart appears to list modifiers to the Perception DC. Is this referring to the DC 20 to know when an invisible creature is within 30 ft., or the check to pinpoint the creature?
I believe it applies to both, and to any relevant situations where you look at the Perception chart.
Does that make more sense?
Okay, the incorrect table entry has already been noted in the errata thread, so hopefully it will be incorporated into the errata soon.
For matching things up with the Perception skill you may want to look at the spell invisibility, which says invisible creatures get a +40 bonus to their Stealth checks, or +20 if they're moving. So it could be that the base DC 20 Perception check to "notice the presence of an active invisible creature within 30 feet" is based on this; you assume the creature has a 0 check result and a +20 bonus? Or a +40 bonus if they're not moving, explaining that DC.I think you found an important typo here: the line for "Not moving" should say +40 rather than -40. It could be someone was looking at the +40 for not moving in the invisibility spell and made a mistake when transcribing the table. But yes, I believe that if an invisible creature is not moving they should be very hard to notice or pinpoint: +40 to the DC to notice them (bringing it to DC 60) or DC 80 to pinpoint their square :P At that point you probably want to break out the glitterdust, a see invisibility spell, a dog with scent, or some other means of assistance.
Thanks, this helped clear things up... But then there's this, given the correction to the typo: say a 1st-level rogue with a Stealth of 9 stands still while sneaking & invisible... That would put the average DC for the Perception roll around 60, the same for a character who's not using Stealth at all, and 50% of the time the rogue would roll worse than average on his Stealth and be worse off than someone not sneaking at all. If their Dex is less than 20 they're worse off than that. Sure, they get progressively better each level, but it still seems strange that a good portion of the time being sneaky makes low-level rogues worse off than someone not even trying.
I think the "not moving" part is a little bit hard, isn't it?
If an invisible creature is in the room and not moving and you want to notice it the DC is 60? That seems to me a little bit too hard. I mean, lets say you role a 20 (which we all know is not that likely). You would still have to have a wisdom score of 32 an be an level 20 rogue with all ranks and a skill focus in perception.
I mean - why shouldn't anyone else be able to hear him breathing or something like that. It should be really hard, but 60 is impossible. I would have suggested something around 40.
I think the "not moving" part is a little bit hard, isn't it? ... It should be really hard, but 60 is impossible. I would have suggested something around 40.
Yeah, I was thinking the same thing. Maybe the entry in the table should read +20 instead of +40? But then again, if you go by the invisibility spell, sensing an invisible creature could be a DC of their Stealth check + 40, and it's not unreasonable for some creatures to be able to get a total of 20 or more on their Stealth checks.
I would guess we wait for the official errata to decide if it should be +40, 40 or Stealth + 40.