Armor

Armor is a mostly obscure stat present on both Survivors and monsters. Having positive armor reduces the damage that character takes, and having negative armor increases the damage taken. This damage modification applies to all damage taken, except for the damage from a Shrine of Blood and damage from Void Fog.

Damage taken is multiplied by $$1 - Armor / (100 + |Armor|)$$. This is a number between 0 and 2.

If a character has positive armor:


 * Damage taken is multiplied by $$100 / (100 + Armor)$$. This is a number between 0 and 1.
 * The formula for the damage reduction is: $$Armor / (100 + Armor)$$.

If a character has negative armor:

The armor value that modifies the damage is a sum of the following contributions:
 * Damage taken is multiplied by $$2 - 100 / (100 - Armor)$$. This is a number between 1 and 2. (Note that the negative armor is subtracted, and two negatives make a positive.)
 * The formula for the damage increase is: $$100 / (100 - Armor) - 1$$.


 * The value of the armor stat (base armor + modifications)
 * +adaptive armor
 * +300 if the character is an and the incoming attack has the AoE damage flag

The modified damage is then decreased by 5 per stack of. Note that the final damage can never be less than 1.

It would take 330 (+30 armor per stack while sprinting) to get a damage reduction of 99% while sprinting. This would amount to 9900 armor. Another way to achieve this amount of armor would be by obtaining 99 to get the same damage reduction while out of combat.

Armor Modifications
Effects that increase a character's armor:


 * Playing on grants each player a hidden item which grants 70 armor.
 * ,, , and each have 20 base armor.
 * has 12 base armor.
 * grants 200 armor while active.
 * grants 100 armor while active.
 * grant 30 armor per stack while sprinting.
 * grants 500 armor while.
 * grants 20 armor while.
 * increase base armor by 10% per stack.
 * grants 100 armor per stack while out of danger.
 * grants 100 armor while corrupted.

Boss Monsters have some base armor. See their individual pages for exact values.


 * life-draining tendrils grant the Dunestrider 200 armor while active.
 * gain 200 armor while looking for an item.
 * gains 200 armor while performing his Shock Wave attack.

Effects that reduce a character's armor:


 * The debuff reduces the victim's armor by 20.
 * reduces targets' armor by 30.
 * inflicts, reducing targets' armor by 60.
 * inflicts, reducing targets' armor permanently by 2 (+2 per stack) on every hit.

Adaptive Armor
and the have the adaptive armor passive stat, which protect them against bursts of damage. Every time they take damage, they gain temporary armor equal to $$3000 \times (damage/maxHP)$$, or 30 armor per 1% of the max HP dealt. This armor caps at 400 and decays at a rate of 40 per second.