Barkskin is a 2nd level spell that lasts up to an hour (no scaling). I would rule it acts as armor only, allowing Dex, shield and whatever other bonuses one would stack with armor.
This. Or look at the unarmored AC boosts for barbarian and monk.
Barkskin isn't just a slight difference in phrasing, that can be chalked up to natural language. It's dramatically different. As I interpret it, then, anything that adds to your AC simply has no effect while you're barkskinned until it exceeds 16. Thus:
Barkskin = AC 16.
Barkskin + Dex 20 = AC 16.
Barkskin + shield = AC 16.
Barkskin + mage armor = AC 16.
Barkskin + shield + mage armor = AC 17.
Barkskin + mage armor + Dex 20 = AC 18.
IOW, your AC is either determined by barkskin or by everything else, whichever is higher.
Druids just don't have good AC, especially the ones who focus on spellcasting. Sure, they're better off than a wizard who doesn't have Mage Armor going, but worse off than anyone who would actually want to be in melee combat.
Well, quite frankly I have no idea where Merric's getting the idea of "Base Armor Class" from... because in the 4 sections in the Index of the PH where Armor Class is mentioned... pages 7, 14, 144, & 177... it only talks about 'Armor Class' There's no mention of a 'Base'... let alone that a 'Base Armor Class' is or would be different than just 'Armor Class'. So I have no idea why Barkskin would be seen as anything other than just a natural armor that mimics the strength of chainmail, and thus you could add and use all the other AC-raising items and conditions on top of it.
A shield would, because shields never factor into your AC. There is no formula for calculating AC which takes a shield into account.As I interpret it, then, anything that adds to your AC simply has no effect while you're barkskinned until it exceeds 16.
A shield would, because shields never factor into your AC. There is no formula for calculating AC which takes a shield into account.
Agreed. I find the phrasing really easy to understand.It says 'Until the spell ends, the target’s skin has a rough, bark-like appearance, and the target’s AC can’t be less than 16, regardless of what kind of armor it is wearing.'
It it worked on your 'Base AC' rather than your 'AC', it would probably have said so.
Agreed. I find the phrasing really easy to understand.
Let's take a few Druids that have cast barkskin:
Druid A is wearing padded leather, have Dex 12, and a shield. Her regular AC is 11+1+2=14.
Druid B is unarmored, have Dex 20. His regular AC is 10+5=15.
Druid C is wearing hide armor, have Dex 16, and a shield. Her regular AC is 12+(max 2)+2=16.
Druid D is enjoying the Mage Armor spell, have Dex 16, and wears a Ring of Protection. His regular AC is 13+3+1=17.
Now, let's see how each of these characters are affected by Barkskin. Remember, the spell's only effect is to say your AC can't be less than 16.
Druid A can't have an AC less than 16, so her AC becomes 16.
Druid B can't have an AC less than 16, so his AC becomes 16. (See how easy this is?)
Druid C already has AC 16, so Barkskin has no particular effect on her: AC 16
Druid D has an AC higher than 16, and Barkskin certainly doesn't lower or restrict your AC, so: AC 17.
Mouseferatu got it right. Only way to be confused is to read things into the spell that isn't there.

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