I was just watching this video from Geek & Sundry while I was preparing some content for tomorrow's session. If you click the link you should be at a specific time in the video. If you watch those couple of seconds the DM says that a natural 20 on perception makes the character learn everything they can about the thing they were trying to figure out.

Recently I asked a similar question here. From the top answer, I understood that only in Combat does a natural 20 mean no-matter-what success. But after hearing what the DM in the video said, I got a little confused. Does Perception have some kind of a special rule? Is it considered an ability check every time you roll for Perception?

I know that this is a very silly question, but I am genuinely confused. Since it is my first time DMing, I want to make sure I know the most basic rules by heart.


6 Answers 6


A natural 20 has no special meaning on a Perception check.

Natural 20s mean nothing special on ability checks (whether or not they are associated with a skill), as already established by your previous question. And Perception is indeed a skill:

The skills related to each ability score are shown in the following list. (No skills are related to Constitution.) See an ability's description in the later sections of this section for examples of how to use a skill associated with an ability.



  • Animal Handling
  • Insight
  • Medicine
  • Perception
  • Survival

A relevant comment from the YouTube video you linked points out that the DM in the video doesn't perfectly adhere to the 5e rules:

Attention New Players!

This video contains rules and/or rulings by the DM that are NOT consistent with the Core D&D 5e rules found in the Player's Handbook. D&D is a game where individual groups can agree on "house rules" that they feel enhance the game experience. However, unless you will be playing exclusively with that group, knowing the rules as suggested by the game designers will be more helpful to you than learning one groups "interpretation" of the rules.

"Starter Kit" the name, may give you the wrong impression that the rules presented here are either the official rules or a simplified version of those rules. What you are actually getting is Jason Charles Miller flavored D&D (which you may find delicious). Be advised that using these rules may conflict with those of another group or DM.

Asked for examples, the commenter provided some in a reply. Another commenter added:

There is also the natural 20 on the perception roll.
In 5e natural 1 and 20 don't affect skill checks or saving throws. Only attack rolls and death saving throws are affected by natural 1 and 20. And this makes sense because no matter what you roll on your strength check you shouldn't be able to lift a castle.

As this comment points out, a natural 1 or a natural 20 has no special meaning on an ability check or saving throw - and Perception checks abide by this rule too.

  • 1
    \$\begingroup\$ It's worth mentioning: This is a common house rule. \$\endgroup\$ Commented Jun 25, 2019 at 23:30
  • \$\begingroup\$ There is the meta game effect, roll 20, and fail, you learn this just aint gonna happen. \$\endgroup\$ Commented Jun 26, 2019 at 20:49

Critical success on a natural 20 is a variant rule from an older edition of D&D.

In D&D 5e, rolling a natural 20 on an ability check, which includes Wisdom (Perception), is neither an automatic success nor an exceptional result. You either beat the check DC or not.

The rules for ability checks are defined in Player's Handbook, Chapter 7: Using Ability Scores, p.174:

As with other d20 rolls, apply bonuses and penalties, and compare the total to the DC. If the total equals or exceeds the DC, the ability check is a success—the creature overcomes the challenge at hand. Otherwise, it's a failure, which means the character makes no progress toward the objective or makes progress combined with a setback determined by the DM.

The DM in the linked video appears to be using a variant rule for critical success, which allows a natural 20 to gain an exceptional result.

The DM may have been inspired by two rules which appeared in Dungeons & Dragons 3.5's Dungeon Master's Guide (2003):

Critical Success or Failure (3.5 DMG p.34):

This D&D 3.5 variant rule allowed skill checks can roll a critical hit on a natural 20 the same way attacks can (thanks to mattdm for noting this variant). An example given by the book:

When using Search, the character discovers something that she otherwise could never have found (if anything is present to be found).

Degrees of Success (3.5 DMG p.32):

A standard rule in D&D 3.5 allowed an especially high roll to have even greater success. An example given by the book:

If the cleric beats the assassin's check result by 10 or more, he has achieved a greater success, and he gets the second answer. If he exceeds the assassin's check result by 20 or more, he has achieved a perfect success and he gets all the information—the third answer.


This is just a houserule

As I stated in the other answer, natural 20 simply indicates the pinnacle of what your character can do, and in a way, the DM of your video indicates that when he says, "you will learn everything you possibly could have learned about whatever you were looking at."

The other players and the DM joke a bit about learning the exact tree the door was made from and the exact name of the architect. These are common, silly extrapolations upon the general notion that you have done as well as you can possibly do. Based upon what the DM actually reveals suggests to me that is absolutely everything he could reveal to the player about the door.

Depending on your table and tone, you may choose to incorporate those silly abstractions or not, but it's entirely table dependent. I've played at tables where there's a long running joke about the piece of cedar that I pried off a door because I was going to prove to the world that it was definitely made by Gerhardt the True, the greatest wood carver of all time; other tables I played at that would've been detracting from the overall story.

  • \$\begingroup\$ This is why we roll only for things which have a non-negligible likelihood of failure, and critical failure/critical success is to be used only if the act is sufficiently dangerous for it to be relevant. Sadly, the latter is often disregarded, and critical failure/success is taken into account whenever dice are rolled. Originally a roll of 1 or 20 wans't critical but under very few very specific circumstances. And it should stay so, otherwise we'll arrive to cases of having a 5% chance during every step in a walk to sprain your ankle or break a leg, and another 5% chance to magically speed up. \$\endgroup\$
    – vsz
    Commented Jun 26, 2019 at 6:08

Does Perception have some kind of a special rule?


Is it considered an ability check every time you roll for Perception?


In the rules there is no rule for a natural 20 on ability checks (Perception or otherwise).

DMs can make one if they want - that is in the rules.


Your prior question's answer is correct; a natural 20 on an ability check has no special effect on the result.

However, the DM on youtube is technically correct... from a certain interpretation of what they said.

The DM's statement that the character learns all they possibly could about what they were trying to perceive is true in the sense that it's not like the character could have rolled better- what that character gets out of the roll is the most that character possibly could have. That does not preclude the possibility of a different character possibly being able to learn even more beyond that if their bonuses are higher.

Of course, the other likely interpretation is that they have a house rule for an automatic success when you nat 20 on an ability check- it's a very common house rule, but a house rule nonetheless.

  • 1
    \$\begingroup\$ The DM's statement was true "from a certain point of view"? That's what you get for gaming with an old Jedi! \$\endgroup\$
    – rosuav
    Commented Jun 26, 2019 at 22:35

There is no special rule for Perception.

The YouTube DM is either a) simply wrong or b) explaining a house rule without explaining that it is one.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .