Talk:Despair/@comment-24.183.39.38-20130623025519/@comment-76.29.53.101-20130624030052

You should probably read this page.

Armor Piercing damage does +50% damage to medium Grineer, -50% damage to light infested, and -50% when hitting the gun barrels of MOA.

It does 100% or more to quite literally everything else.

Sounds about right to me.