Fortitude

Check
You may check whether or not your reflex can Block the action unit's basic attack or Melee ability when responding to an attack. Before damage calculation, you may choose to Block, Dodge, Oppose, or perform a defensive ability. The DC of the check equals the attack damage roll of the action unit. The responding unit must meet or surpass the DC with the check (d10 + Fort) in order to block it. A Block check requires a shield equipped.

If the Block check fails, check whether or not the shield is destroyed with d20 + AP of shield against the action unit's attack damage roll. If the check does not meet or surpass the attack damage roll, the shield is destroyed.