Armor (referred to as Armored in some card text) is a keyword effect in Bloons Card Storm. When a Bloon with Armor takes damage from any source, the damage is reduced by the amount of Armor the Bloon has. If a source of damage is less than or equal to a Bloon's Armor, that Bloon takes zero damage. Armor does not affect Shields.
Some Bloons have Armor by default. Certain cards can apply Armor to other Bloons. A white number on an icon of a metallic plate indicates the amount of Armor on a Bloon.
None of the playable Heroes are able to gain Armor, but Dreadbloon can give itself Armor by using its Armored card.
Armor-Piercing MOAB Mauler targeting a Lead Bloon. If it attacks, it will remove all of this Bloon's Armor before dealing 65 damage.
Armor Piercing (formatted as Armor-Piercing in some card text) is a keyword effect that causes a Monkey to strip all Armor from a target Bloon or Boss Bloon before calculating and applying damage, even if it has a Shield or is immune to damage (e.g., Dreadbloon using Immunity), and regardless of ATK (e.g., Buddy Bloon's 0 ATK debuff). Some Monkeys with Armor Piercing have additional effects, such as the Lead to Gold Monkey.
Splash Damage not counting for Armor Piercing