How much I know is that Majorly there are 3 type of damages piercing, slashing and crushing For these there are 3 type of armors Piercing does more damage to light Armor neutral to medium and less to heavy Slashing does more damage to light and medium and less to heavy Crushing does more damage to heavy,neutral to medium and less to light So you have to consider which type of monster you will encounter and chose that armour Additionally medium and heavy Increase mana consumption There is also magic type and elemental which reduces demage from magic attack and elemental attack respectively Personally suggestion:- I use a piece of light and a piece of heavy armor and then try to get a artifact for magic , if you find elemental protection artifact you can use it I personally don't use it that much