Second Skin

Your runed armor has an uncanny ability to protect your life.

Prerequisites: Dwarf, Runed Armor

Benefit: When you would be struck by a critical hit, you can take the blow on your runed armor or shield instead. Your armor is badly damaged (usually doubling its check penalty and halving its AC bonus), but the blow is reduced to a normal strike. 

If you fail a save against a damaging attack that deals reduced damage on a successful save, your armor can take the damage instead (effectively granting you a successful save).

Reduce the check penalty of your favored armor by 2 (to a minimum of zero).