What are Difficulty Classes?
In a previous post, I also mentioned something called “DC”, which is a number that the DM sets for you to beat with your dice roll.
Your character also has its own DCs, which are the numbers your opponent needs to beat to either hit you, to sneak past you, or to avoid damage & effects from your attacks.
Here are the types of Difficulty Classes on your Character Sheet:
Armor Class
“Armor Class” represents your Armor, and/or how hard you are to hit. It’s the number your enemy needs to beat with their Attack Roll so that they can hit you. It should be around the top portion of your Character Sheet, and indicated by the words “Armor Class” or “AC”.
As an example of Armor Class in action:
As your party is travelling to another town to seek out better jobs, you come across a band of bandits. They are blocking the road, and asking for a toll fee of 5 Gold Pieces. Your party is poor, so you all refuse to pay the “toll”, and insult the lead bandit.
He promptly lifts up his crossbow, and fires at your scrawny little Wizard. (Sometimes DMs will bypass Initiative rolls for the sake of the story.) The Wizard freaks out, because he doesn’t have Mage Armor on, and his AC is only 13 without it. (Mage Armor is a spell that bumps his AC up to 16; more on Spells in a future post.)
Despite your Wizard’s protests, your DM makes an Attack Roll for the bandit: d20+3. His d20 roll comes up 6, which brings his roll up to 9. Since the Wizard’s AC is 13, the bandit misses him. Your DM then narrates that because the Wizard was so paralyzed with fear, holding very, very still, the bandit’s aim adjustment made him miss, and the crossbow bolt embeds itself on a nearby tree.
Passive Perception.
“Passive Perception” represents your character’s ability to passively notice things in their surroundings. Your DM will usually use this number to roll against when making Stealth checks for your enemies. It may appear in different places on different Character Sheet designs, but it may be denoted as “Passive Perception” or just the word “Passive”.
Passive Perception in action:
You and your party are walking uphill on a rocky landscape, using boulders and small shrubs as handholds and footholds to help you on your hike. In the middle of narrating this scene, your DM rolls his dice out of nowhere, and asks all of you for your Passive Perceptions.
Your party is on edge as you tell him all your scores:
You say you have 10.
Your Wizard says he has 12.
Your Barbarian says she has 13.
Your Paladin says she has 10.Your Druid, however, says she has 16.
Behind the DM screen¹, your DM secretly rolled a 15 Stealth check. He reveals to your Druid that she sees something in the corner of her eye, moving among the shrubbery. It has a low crouch, and is lurking among the vegetation.
Your DM finally says definitively that she is staring into the golden-orange eyes of a very large mountain lion. He gives her (and only her) a chance to do something before he asks everyone to roll Initiative.
Feature Save DCs.
Feature Save DCs are slightly more complex to explain, because there are different Features across different classes. When your character has a Feature, you can read through the Feature description to see if that Feature has a DC. But for the purposes of this tutorial, I’ll explain the DC for the Monk’s “Ki” Feature.
The formula for the Monk’s Ki DC is:
8 (Fixed) + Wisdom Modifier + Proficiency Bonus = Ki DC
Let’s say the Monk’s Wisdom Modifier is +3, and his Proficiency Bonus is +2. That would make the calculation look like this:
8 + 3 (WIS Mod) + 2 (Prof Bonus) = 13 (Ki DC)
📌 If you are playing a Monk, once you calculate this, you should note this down somewhere on your character sheet, so you don’t have to keep calculating it every time your DM asks for it.
The Monk’s Ki DC in action:
During your skirmish with the bandits, you see your Monk bravely charge at their leader, and you sense a powerful energy surrounding her body. She makes an attack, and tells the DM that she’ll spend 1 Ki Point to activate Flurry of Blows, giving her 2 more unarmed strikes with her Bonus Action. The DM tells her to make 3 Attack Rolls; one for her normal attack, and two more for her Flurry of Blows. All three of her attacks hit.
She then decides to try and knock the lead bandit over with her Open Hand Technique. The DM asks her what her Ki Save DC is. She answers, 13. The DM rolls a Dexterity Saving Throw for the bandit: d20+3—it comes up 7; he fails.
The DM then narrates her attack; all of your party members could barely see her fists flying through the air—2 hits land squarely on the torso of the bandit, knocking the wind out of him. And the third was a sweep kick, knocking his legs out from underneath him, and he falls over, knocked prone.
You see your Barbarian standing right beside him drenched in the blood of his companions. You watch as she grins at him evilly with a glint in her eyes².
In summary:
- There are 3 types of standard Character DC’s—Armor Class (AC), Passive Perception, and Feature Save DCs.
- Armor Class (AC) is the number your opponents have to roll against to hit you.
- Passive Perception is the number your opponents have to roll against to sneak past you, or up to you.
- Feature Save DCs are different for every class, but this is the number opponents have to roll against to prevent the Feature’s effect from applying to them.
Next up: What are Hit Points & Hit Dice? (Under Construction)
Footnotes:
¹ ^ The DM Screen is traditionally used to hide the DM’s tools from the players.
² ^ When an opponent is knocked prone, a melee (not ranged) attack roll is made with Advantage. You roll a d20 twice, and take the higher roll to add to your attack modifier. Conversely, Disadvantage means you roll a d20 twice, and take the lower roll.