Why isn't Mage Armor working on Unarmored Monks?

[Dies Horribly]

Guessing it won't work on Unarmored Barbs either...
Is this a bug or is it intended for balancing reasons?
If it's for balance (you can have a lvl 1 monk with AC 19 with the help of a wizard), why not have the monks get an Improved Unarmored Defence at around 4th/5th level, which would make it stack with Mage Armor? Around those levels you can already have fighters easily go AC 19/20. Same with a monk with Mage Armor...
Plus, that Mage Armor requires concentration, which means you can't have your wizard do any other enhancements on any others...

[Tario]

you can use only one ac calculator.
You use either
- Armor + Dex (light + medium)
- Armor (heavy)
- Barbarian (Con+Dex)
- Monk (Dex+Wis)
- Mage armor (13+dex)
- Barkskin Spell (16)
You get the idea. IF you use mage armor, you dont use your monk unarmored defense feature.

[Daniel_USA]

your monk unarmored is probably higher then mage armor

[BigJ]

Mage armour counts as armour, disabling your unarmored defense. (it picks the highest)
Same with sorcerers with draconic bloodline.

[Dies Horribly]

Originally posted by BigJ:

Mage armour counts as armour, disabling your unarmored defense. (it picks the highest)
Same with sorcerers with draconic bloodline.

That makes sense, I guess...

[Humble]

It's might work in older rule, I think but now this case, it's won't work, they make sure of it, careful with all bunch of rule ensure no one exploit or abused system, I guess. Know Larian Studios, they don't like powerful or overpower, so that is why we can't had a good overpower stuff build, if they knew there is overpower that they are not aware of it, they would nerfed or change rule.

[Agony_Aunt]

Originally posted by Tario:

you can use only one ac calculator.
You use either
- Armor + Dex (light + medium)
- Armor (heavy)
- Barbarian (Con+Dex)
- Monk (Dex+Wis)
- Mage armor (13+dex)
- Barkskin Spell (16)
You get the idea. IF you use mage armor, you dont use your monk unarmored defense feature.

Barbarian CON and Monk WIS don't stack? Damn, there goes an idea I had! Works in Pathfinder... and i think in Solasta.

[Sentient_Toaster]

Correct, they don't stack.

In fact, at least in tabletop -- you only get the Unarmored Defense feature from whichever class you take first. The second one isn't available as a choice even if it for some reason would give a better armor class (maybe you have a strong preference in DEX vs CON save proficiency or in the possible skill proficiencies but otherwise want to focus on the other class, I guess?).