Armor

Armor has hit points that weapons must first break down before they can properly injure your body.

Padded: 6 hp
Leather: 12 hp, -1 to casting
Chainmail: 24 hp, -2 to casting
Plate: 36 hp, movement decreased by 5', may not cast

Shields have both hit points and a defense bonus.

Buckler: 4 hp, +1 defense
Wooden: 6 hp, +1 defense
Metal: 8 hp, +1 defense
Tower: 12 hp, +2 defense, movement decreased by 10'
Dual-Wielding*: +1 defense, +1 damage to larger die

*Dual-wielding weapons does not grant a shield's hp bonus.