Armor penetration

Armor Penetration gives a damage boost.

The higher a playrs AL is the lower is the foes boost by armor penetration.

Armor penetration with Armor Level:
Armor Penetration lenghtens the Half life of the inflicted damage per armor level and increases the required AL to let 100% of the inflicted damage trough.

With 0% Armor Penetation:

 * 60 AL lets 100% of the inflicted damage through.
 * 100 AL (60+40) lets 50% of the inflicted damage through.
 * 140 AL (60+40+40) lets 25% of the inflicted damage through.
 * The "AL half life" is +40 AL (known by most players).

With 10% Armor Penetraton:

 * 67 armor lets ~100% of the inflicted damage through.
 * 111 (67+44) armor lets ~50% of the inflicted damage through.
 * 155 (67+44+44) armor lets ~25% of the inflicted damage through.
 * The "AL half life" is ~ +44 AL.

With 20% Armor Penetraton:

 * 75 armor lets 100% of the inflicted damage through.
 * 125 (75+50) armor lets 50% of the inflicted damage through.
 * 175 (75+50+50) armor lets 25% of the inflicted damage through.
 * The "AL half life" is +50 AL.

With 25% Armor Penetration:

 * 80 armor lets 100% of the inflicted damage through.
 * 133 (75+53) armor lets ~50% of the inflicted damage thhrough.
 * 186 (75+53+53) armor lets ~25% of the inflicted damage through.
 * The "AL half life" is ~ +53 AL.

The formular for weapon damage is:

 * If attribute skill <=12:
 * actual_damage = Damage*(Damage_bonus/100+1)*2 ^ ((5*(Attribute_skill -AL*(1-Armor_penetration/100)) -60) /40)
 * If Attribute Skill >12:
 * actual_damage = Damage*(Damage_bonus/100+1)*2 ^ ((5*(Attribute_skill -AL*(1-Armor_penetration/100)) -60 -(Attribute_skill-13)*2,5) /50)

and for skill damage:
 * actual_damage = Damage*2^ ((caster_level*3 -AL*(1-penetration/100))/40)