Engrave Chest - Shield Mastery

Engrave your chest or robe with the Shield Mastery rune: Each time you Block, you regenerate mana equal to 8% of your maximum mana and you gain Armor equal to 30% of your shield's armor value, stacking up to 5 times. You also always gain 10% increased chance to Block and 15% increased Block value. In addition, each time you use a Shock ability, you gain 4 Spell Damage for each point of your defense skill beyond 300. Lasts 15 sec.