curious natural armor question?

[fel_horfrost]

I have an half orc with the iron hide feat that grants a +1 natural armor bonus and
The mutagen class feature which grants a +2 bonus to natural armor bonus and the feat improved natural armor twice. Pre mutagen i have a +3 natural ac when i drink the mutagen do i now have a +3, +4, or +5 natural ac? I'm not sure if the any of it stacks or if the bonus from the mutagen ignores the ironskin bonus.

[dragonhunterq]

The mutagen is an untyped bonus from a different source to the ironhide feat so should stack. Improved natural armour would be kind of pointless if that didn't stack. So I make that +5 natural ac.

[Nefreet]

Mutagen grants you a +2 Natural Armor bonus.

Ironhide grants you a +1 Natural Armor bonus.

These two do not stack. Only Dodge, Racial, and (most) Circumstance bonuses stack. Natural Armor bonuses do not stack.

With Ironhide, your base Natural Armor bonus is +1. When you drink your Mutagen, the +2 overlaps the +1.

If the Mutagen provided an Enhancement bonus to your existing Natural Armor, then the two would stack.

Improved Natural Armor stacks with both of these. If you've taken the feat twice, then your base Natural Armor bonus will be +3. With Mutagen, it will increase to +4.

[fel_horfrost]

Then it seems ironhide is a necessary evil as you cannot pick up improved natural armor without a natural armor bonus to start with. I will pick up the greater and grand mutagen discoveries later and improved natural armor multiple times.
A amulet of natural armor is also in the works so it seems that I'll rocking natural armor equivalent the fullplate at some point.

[Nefreet]

The really cool thing is that all that Natural Armor stacks with regular Armor (like Fullplate).

[fel_horfrost]

Yes, yes it does but my touch ac is going to be garbage though.
On a non casting character not sure how to raise it.
On the plus side natural armor does count against brilliant energy weapons though.

[Sir Eldon's Head]

The mutagen grants an alchemical bonus to nature armor. Iron hide gives a +1 bonus. Improved natural armor increases the bonus by 1 each time you take it. They all stack. They also stack with the amulet of natural armor which gives an enhancement bonus.

[Splendor]

RAW the bonus to NA isn't listed as alchemical, thus doesn't stack.

Quote:

Upon being imbibed, the mutagen causes the alchemist to grow bulkier and more bestial, granting him a +2 natural armor bonus and a +4 alchemical bonus to the selected ability score...

The stat bonus is called out as being a alchemical bonus but the NA isn't.

The reason a amulet of natural armor stacks is because of the barkskin spell.

Quote:

Barkskin toughens a creature's skin. The effect grants a +2 enhancement bonus to the creature's existing natural armor bonus.

The Barkskin spell is a 2nd level alchemist spell.

If you took the Racial Heritage feat, which half-orcs can take, you could choose Tiefling and take Armor of the Pit.
In a couple levels you could take History of scars.

[Durngrun Stonebreaker]

Tieflings are outsiders, not humanoids.

[Splendor]

Sorry, you are correct about tieflings, I see people say 'Racial Heritage: Tiefling' so often on the boards I though it was correct.

[Lord Lupus the Grey]

Does history of scars stack with racial natural armor bonus?

What about dragond disciple with history of scars?

[Syries]

Untyped bonuses from different sources stack. Nat A.C. from a feat and nat A.C. from mutagen are different sources, therefore they stack. Nat A.C. from multiple different feats stack, for that matter.
But something like an amulet of nat a.c. and Barkskin don't stack because the source is an enhancement bonus.
A dwarf alchemist can get crazy high nat a.c. with iron hide, improved natural armor, bone spike mutagen, barkskin extract, and +1/4 nay a.c. from mutagen with the favored class. All those together at level 8 puts you at +11 nat A.C.

Edit: I really need to pay more attention to the timestamps on these forums.
Dragon disciple Nat a.c. increase stack with all other types, as it specifies it is an increase to any racial nat a.c. you already have, if any. I don't know of any way, but I suppose of you had some other way of increasing your racial bonus, it wouldn't stack with the DD bonus. History of Scars would stack as well, as they are different sources