I have long assumed that this kind of perception check would be done with Disadvantage due to the inability to see the creature invisible, but after further investigation of the rules, I can not find any evidence that this is the case and I & # 39; We had trouble finding questions on this pile that clearly deal with this case. Many answers presuppose that the audit is done with a disadvantage, without proving or questioning it, without asking whether this is the case.
To criticize nothing, FYI, because it is not the purpose of this answer.
Here's why I believe the check is not done with Disadvantage.
the Invisible condition does not expressly state that it confers a disadvantage to the perception checks
- An invisible creature is impossible to see without the aid of magic or a special meaning. In order to hide, the creature is heavily obscured. The position of the creature can be detected by the noise or tracks it leaves.
- The attack rolls against the creature have a disadvantage and the creature's attack rolls have an advantage.
–Invisible, PHB, pg. 291
You may be wondering, dear reader, if the bold part (underscores are underlined) about the invisible creature counting as "very obscure" should prove that this check must absolutely be done with Disadvantage. After all, Heavy occultation says that creatures have a disadvantage on perception tests, right?
The rules regarding heavy obscuration do not say that they confer a disadvantage to perception checks
In a slightly obscure arealike a dim light, thick fog or moderate foliage, the creatures have a disadvantage on the wisdom controls (perception) which depend on the sight.
A very dark area– like darkness, opaque fog or dense foliage – completely blocks vision. A creature in a very dark area actually suffers from the blind condition (see the appendix). A very darkened area does not blind you, but you are actually blinded when you try to see something that is obscured.
–Light and vision, PHB, pg. 183
A blind creature is described as an automatic failure of any control that requires vision; but he makes no mention of the drawback checks on the ability that simply use the vision (Search hearing, smell, etc. in addition to the vision):
- A blind creature can not see and automatically fails any ability check that requires sight.
- The attack rolls against the creature have an advantage and the creature's attack rolls have a disadvantage.
–Blinded, PHB, pg. 290
And just to be sure to leave nothing to chance, the Perception competence does not expressly call Disadvantage on checks that require multiple meanings but for which only one meaning is functional:
Verifying your wisdom (perception) allows you to spot, hear or detect the presence of something. It measures your general awareness of your environment and the liveliness of your senses.
–Verifications of wisdom, PHB, pg. 178
The rules for perceptual hidden creatures mention a visual impairment such as a faint light or fog, but not invisibility.
What can you see? One of the main factors in determining whether you can find a creature or a hidden object is the quality of your vision in an area that may be slightly or heavily obscured, as explained in Chapter 8.
–Hidden, PHB, pg. 177
I want to make a comment about this especially because detecting an invisible creature is not just about seeing it, but also about detecting evidence of that. Things like footprints or disturbed dust on the floor. Elements that would necessarily be more difficult to detect in a dark room or in the dark than under bright light. And of course, there is also the problem of trying to hear or feel an Invisible + Hidden creature, neither of which is weakened by vision.
The rules for Hidden call out Invisibility as a way to guarantee the option to hide, but do not cite any benefit to the check
You can not hide from a creature who can see you clearly and if you make noise (like shouting a warning or flipping a vase), you give your position. An invisible creature can not be seen, so she can always try to hide. Signs of his passing could nevertheless be noticed and he must still remain silent.
–Hidden, PHB, pg. 177
I mean, it's really weird, right, if an invisible creature does not really disadvantage attempts to detect it? If the specter of these perception checks is really just the binary of
- Make the check without inconvenience, or
- Automatic failure of verification, due to effects like Pass without trace and or Silence, suppressing both auditory and other tertiary effects that could leave traces, leaving only the [in-]ability to actually see the Invisible target
But if there is evidence that definitely refutes this reading, I have not found it.
Addendum: the creature is still "invisible" and still gives Disadvantage / Advantage rolls to the attack
For this to not be undone, none of this allows a creature to "see" an invisible creature. As far as I know, this has not been violated by my understanding of the rules. The only thing that has happened is that the location of the invisible creature has been detected (or not detected) based on the results of the perception check.