I've been tearing my hair out for a hot minute, trying to figure this out. I have a homebrew race that I would like to have a kind of natural armor. This is what I've done:

• Set - Minimum Base Armor 16
• Set - Unarmored Armor Class CON
• Ignore - Unarmored Dex AC Bonus 
• Set - AC Max Dex Armored Modifier 0
• Set - AC Max Dex Modifier 0
• Set - AC Max Dex Unarmored Modifier 0

Basically, I want remove any AC bonus from DEX and switch it out for CON. I want them to receive the most benefit from going unarmored. To that point would holding a shield be considered "armored?"

If what you want is to swap out Dex for Con as far as their Unarmored AC goes, you can get rid of almost all of that. All you need are these two modifiers:

• Modifier: Ignore->Subtype: Unarmored Dex AC Bonus
• Modifier: Set->Subtype: Unarmored Armor Class->Ability Score: Con

That’s it, that’s all it takes. That will give those characters the following unarmored AC Calculation: (10 + Con mod).

If instead you want the following calculation: (16 + Con mod), then simply alter the second Modifier to the following:

• Modifier: Set->Subtype: Unarmored Armor Class->Ability Score: Con->Fixed Value: 6

After you save the Modifiers, you MUST re-save the entire homebrew using the main [SAVE CHANGES] button under Basic Information or the system will not pick up those changes. Then be patient, it can take up to 20 minutes for those changes to push through to the character sheet/builder.

No, a shield does not count as armor in this case, it only counts as armor for Monks, and for donning/doffing.

Quote from IamSposta >>

If what you want is to swap out Dex for Con as far as their Unarmored AC goes, you can get rid of almost all of that. All you need are these two modifiers:

• Modifier: Ignore->Subtype: Unarmored Dex AC Bonus
• Modifier: Set->Subtype: Unarmored Armor Class->Ability Score: Con

That’s it, that’s all it takes. That will give those characters the following unarmored AC Calculation: (10 + Con mod).

If instead you want the following calculation: (16 + Con mod), then simply alter the second Modifier to the following:

• Modifier: Set->Subtype: Unarmored Armor Class->Ability Score: Con->Fixed Value: 6

After you save the Modifiers, you MUST re-save the entire homebrew using the main [SAVE CHANGES] button under Basic Information or the system will not pick up those changes. Then be patient, it can take up to 20 minutes for those changes to push through to the character sheet/builder.

No, a shield does not count as armor in this case, it only counts as armor for Monks, and for donning/doffing.

 Thanks, that did it. I was in deep and getting confused.

One more question. Is there a way to prevent armor from adding AC?

Don’t wear any armor...?

The way AC works in D&D is through “calculations.” Armor doesn’t ever “add AC,” what it does is provide an alternative calculation.

• A normal character as an Unarmored AC of “10 + Dex mod.”
• Your Homebrew would replace that calculation with ”16 + Con mod.”
• If they are wearing Studded Leather armor, that gives them an alternate calculation of “12 + Dex mod.”
• If they are wearing +1 Studded Leather armor they would grant an alternate calculation of “13 + Dex mod.”
• If they were wearing Plate that grants an alternate calculation of “18.”

The way DDB is programmed, it uses whichever calculation is highest of the “equipped” options. So, if a character using your homebrew were to don a suite of +1 Studded Leather armor, the system would compare the two available calculations (16 + Con mod) vs (13 + Dex mod) and use whichever of the two provides the highest AC for that character. If that same character were to also don a suit of Plate armor too,* then it would compare all three options (16 + Con mod) vs (13 + Dex mod) vs (18) and use the highest option.
   *(Yes, that would be ridiculous IRL, but it is technically possible to do on the DDB character sheet because of technical system limitations.)

A Shield adds a +2 bonus to whichever AC Calculation the Character is using at the time. (If it was a Shield, +1 then it would add +3 bonus instead.) Whereas something like Bracers of Defense adds a +2 AC, but only to a character’s Unarmored AC calculation.

Does that make sense?

Quote from IamSposta >>

Does that make sense?

Very enlightening. Thank you for the clarification.

btw, Is there a guide that you recommend for homebrew creations here on ddb?

edit: Nevermind, I see you have them in your sig.

As usual, happy to help.

Yup, stuck those links there for stuff exactly this.

And if you ever need help, just post in the Homebrew form. Someone will see it and offer whatever help we can.