Morph Shell (3.5e Feat)
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Morph Shell [Special]
Tougher skin with scales, furs, etc.
Prerequisite: Must be able to change shape in one of the following five ways: change shape supernatural ability, shapechanger subtype, polymorph as a spell-like ability, able to cast the polymorph spell, wild shape or similar class feature
Benefit: You gain 1 point of natural armor to Armor Class. You can also chose to sacrifice 1 point of attack bonus to increase natural armor by 1 point. You can do this as a part of a swift action.
Special: This feat can be taken up to 3 times. Even if you take this feat more than once, you can only convert 1 point of attack bonus into 1 point of natural armor. If you cast the polymorph spell, has polymorph as a spell-like ability usable less often than at will, or has the wild shape class feature, then this feat loses function when you cannot use them.