Every form of damage in the game is linked to an attack type, and the damage a unit receives is modified in accordance with its defense type. This chart illustrates the multiplier each attack types uses against each defense type.

Power armored units use either the Power Armor or Power Armor MkII defense type, although uses the Thick Skin defense type like other bosses. Most enemies use the Melee¹ attack type. Bosses, , and use the Melee² attack type. Weapon-skill damage uses the attack type of the . Damage from other sources usually uses either the Explosion or Melee¹ attack type.