Why doesn’t natural armor stack with certain class bonuses? Like lizard folks natural armor bonus and a barbarian ac boost from con? Does the lizard folk just develop thinner skin? 1. Simplicity
2. Stacking several would be too much.The lizardfolk would get to choose which of those AC calculations to use per PHB pg 14. If their natural armor is better than Unarmored Defense, they're free to use that!
— Dan Dillon 👥 (@Dan_Dillon_1) January 27, 2020
“1. Simplicity”
“2. Stacking several would be too much.”
Human Cleric: I equip my plate armor.
DM: Alright, that’s AC 18.
Human Cleric: Also I grab my shield.
DM: Okay, that’s +2 for 20 AC.
Human Cleric: Oh, no – I meant my magic shield.
DM: Alright, so that’s +2, and then another +1, on top of 18, for 21 AC.
Human Cleric: Also I cast Shield of Faith.
DM: Sure – that’s 18 + 2 + 1 + 2 for 23 AC.
Human Cleric: Also, I’m keeping a spell slot ready to cast Shield when I get hit.
DM: So that’ll be 18 + 2 + 1 + 2 + 5, for a total of 28 AC the first time you get hit.
Lizardfolk Rogue: I equip my studded leather armor.
DM: Alright, your AC is now 12 + your Dexterity bonus of 4.
Lizardfolk Rogue: Wait… don’t I have natural armor? I add my Constitution too.
DM: Are you crazy? That’s WAY too complicated! Stacking would be too much!
*eyeroll*
Are you implying that stacking natural armor and Con bonus on top of plate + shield + spells would somehow be less complicated?
Because you’re kind of illustrating the exact point Dan was making; there’s already tons of things that stack AC. The line has to be drawn somewhere, and letting more and more things stack would lead to the 40+ ACs that existed in 3rd edition.