Armor

Armor decreases the non Spell Damage Units take by one per Armor point.

Overview


Armor is a unit property which reduces incoming damage by one per Armor Level. This is not to be confused with Armor Upgrade Level, which is a counter of how many times the Armor of a unit has been upgraded. Armor may be upgraded at certain structures, and can make a significant difference in what units counter what.

Units that do low damage are most penalized by attacking a target with high Armor, because it reduces a larger percentage of the overall damage dealt. All attacks will do a minimum of .5 Damage, even if the Armor is higher than the attack's Damage. However, some special attacks ignore Armor, and all Spells ignore Armor.

A Unit's base Armor can be quickly determined by checking it's Unit Tag. Light Units have zero base armor, Medium one, and Heavy two.

Formula
The formula for Damage dealt after Armor is this:

(Paper Damage x Number of Hits) - (Armor Level x Number of Hits) = Actual Damage Dealt

For example, a Zergling attacks a Firebat. The Zergling attack deals four damage in one hit on paper, and the Firebat has one base Armor. The actual Damage dealt is three, as shown here:

[4 (Zergling Damage) x 1 Hit] - [1 (Firebat Armor) x 1 Hit] = 3 (Actual Damage Dealt)

Armor Upgrades are also very significant. Upgraded Weapons can reduce the number of hits it takes to kill a unit, and upgrading the unit's Armor in response can counter this. For example, Zerglings die to Zealots in two hits instead of three if the Zealots have one Weapon Upgrade and the Zerglings have no Armor Upgrade. The base fight looks like this:

[8 (Zealot Damage) x 2 Hits] - [0 (Zergling Armor) x 2 Hits] = 16 (Actual Damage Dealt)

Zerglings have 35 HP, so doing this three times will kill them. Now, a Zealot with one Attack Upgrade fighting a Zergling with no Armor Upgrades looks like this:

[9 (Zealot Damage) x 2 Hits] - [0 (Zergling Armor) x 2 Hits] = 18 (Actual Damage Dealt)

Doing this twice will deal 36 damage, enough to kill a Zergling, and completely change the landscape of the unit interaction.