The Fae have always been divided between the summer and winter fae. Those in the winter may call upon dark forces in times of need and Patrick has picked this up as well now. His ears lengthen and his nails and teeth sharpen and he looks more animalistic then human when he activates it to defend from most things.
You have 3 Armor, which reduces incoming Damage. Armor from multiple sources does not stack. Passive, always in effect.