Dungeons & Dragons: Rules Answers January 2015


The Dungeonmaster is back! – WotC answers a bunch of rules questions to keep your D&D adventures rolling along.  Come see:

This month’s installment covers:

  • Character Creation
  • Spells

Here’s just a handful of samples to get you going:

How do you calculate a creature’s Armor Class (AC)?

Chapter 1 of the Player’s Handbook (p. 14) describes how to determine AC, yet AC calculations generate questions frequently. That fact isn’t too surprising, given the number of ways the game gives you to change your AC!

    Here are some ways to calculate your base AC:

  • Unarmored: 10 + your Dexterity modifier.
  • Armored: Use the AC entry for the armor you’re wearing (see PH, 145). For example, in leather armor, you calculate your AC as 11 + your Dexterity modifier, and in chain mail, your AC is simply 16.
  • Unarmored Defense (Barbarian): 10 + your Dexterity modifier + your Constitution modifier.
  • Unarmored Defense (Monk): 10 + your Dexterity modifier + your Wisdom modifier.
  • Draconic Resilience (Sorcerer): 13 + your Dexterity modifier.
  • Natural Armor: 10 + your Dexterity modifier + your natural armor bonus. This is a calculation method typically used only by monsters and NPCs, although it is also relevant to a druid or another character who assumes a form that has natural armor.

Does Unarmored Defense work with a spell like mage armor?

Unarmored Defense doesn’t work with mage armor. You might be asking yourself, “Why don’t they work together? Mage armor specifies that it works on a creature who isn’t wearing armor.” It’s true that the target of mage armor must be unarmored, but mage armor gives you a new way to calculate your AC (13 + your Dexterity modifier) and is therefore incompatible with Unarmored Defense or any other feature that provides an AC calculation.

Read the entire Q&A Here:

Sage Advice Compendium: January 2015

~Happy adventuring!


  • Does Unarmored Defense work with a spell like mage armor?

    The DM says it doesn’t. Only answer that needs to be given 😉

    • Xodis

      That and the fact the PHB clearly outlines that they dont.

      • DM>PHB
        but yes, there is always that.

        • Xodis

          I agree with that, I’m just saying its not like a DM even needs to make that decision, people just need to read the book lol.

          • Reading…what is this “reading u speak of?” every group I ever DMd for seems to have forgotten how LOL