The armor in CS2 absorbs a certain percentage of the damage dealt by a weapon. The exact percentage differs depending on the weapon. It doesn't matter how many armor points are left, the absorbed damage always remains the same as long as the armor wear is above 0.
Armor should always be bought when the remaining armor value threatens to fall below 0 in the next round. As a guideline from about 33 remaining armor own armor must be renewed.
How does the armor work in CS2?
Armor in Counter-Strike does not function as a pure shield as it does in other games. In CS2, a certain percentage of the damage is absorbed by the armor and the remaining armor is reduced. The percentage of damage absorbed depends on the weapon.
Another big advantage besides the damage absorption is that the crosshair recoil is reduced when you are hit. Armor with a helmet even eliminates this recoil completely.
When to buy a helmet?
In some cases it makes sense not to buy a helmet. For example, it makes sense if you don't have enough money to buy one, but your team does and your opponents are playing AK-47s anyway, so a headshot is a one-hit shot.
However, if your opponents are playing MP's you should always make sure you have a helmet, as the damage from MP's is significantly reduced.
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