I play a Tortle Draconic Bloodline sorcerer, and my DM and myself are scratching our heads on what its AC total should be.
The Draconic Bloodline sorcerer gets an AC of 13 + Dex, but Tortles get an AC of 17 flat with no Dex mod. I have a shield (which gives a +2 bonus), so I think total is either 22 or 24.
Is my AC calculation correct? If not, how should I be calculating my AC?
Best Answer
You must use one formula for calculating your AC
If your character happens to have multiple given formulas for calculating their armour class, due to their combination of racial traits, class features or equipment, you don't get to mash them all together. At any given time, you pick one basic formula and use that (ideally, choose whichever one gives you best AC).
As per the basic rules:
In your tortle's case, unless your dexterity bonus is better than a +4, there's no advantage to using the Draconic Bloodline feature to calculate your AC - it will be equal to or worse than 17, which is the default AC for the tortle. However, your shield offers a flat bonus to AC which is applied after figuring out your base AC, so you can always benefit from that no matter which basic AC formula you use. Assuming your dexterity modifier isn't that high, your tortle's AC should be 19.
You don't have to stick with the choice permanently - you can change which one you're using if it would be better for some reason. For instance, if your tortle received a buff which raised your dexterity score to 20 (or higher), the +5 modifier means it would now be better to calculate your AC using your bloodline feature, so you can decide to start using that instead - and of course you can use the old method again once the buff wears off and your dexterity drops. The game doesn't impose any conditions on when you can choose or change your choice, so you can recalculate your AC whenever it's relevant.
A useful way to interpret these rules might be that all of those formulas are actually always in effect, but they overlap, not stack. The final AC the character actually has at any given moment is simply determined by whichever formula produces the highest number, as the most powerful effect (assuming, of course, you want your character to have the best AC they can!)