When your health goes below the half, you are seriously wounded. The game slows down for a while, the camera moves around a bit, like when you are drunk ( so it´s difficult to aim accurately ), you bleed and lose health slowly. When you get your health back up above the half, you are okay again.
If you would like to include this in your mod, modify it or something, contact me. But there is always a rule, when you use my mods in your mod, you have to mention it.
( like: Woundmod by Itawwwa )
Installation: Copy Woundmod.cs into your "cleo" directory