护甲 (EN:Armor ) is a form of secondary Health available only to heroes, gained through certain spells, Hero Powers and minions. Damage taken will always be deducted from Armor before Health. Only when a character has 0 Armor will they lose Health from a damaging attack. Armor can effectively extend a hero's Health far beyond the 30 points otherwise allowed. All regular heroes enter play with 0 Armor, although bosses and Tavern Brawl heroes often start with some Armor.
Sources of Armor include the warrior Hero Power Armor Up!, the druid Hero Power Shapeshift, the mage Secret Ice Barrier and the warrior minion Armorsmith. Some cards have more novel relationships with Armor, such as Shield Slam, which uses a warrior's Armor to deal damage to a target minion.
When present, Armor is shown on the centre right of the hero, just above the Health icon, set against a silver, unbroken shield.
Armor is most strongly associated with the warrior class, followed by the druid class.