There is a great guide posted over on the vaingloryfire forums looking at the math behind the how weapon and crystal damage is calculated.
From the guide:
In general, the damage a hero does with his/her basic attack – when they are attacking without using any
abilities – is calculated as follows.
Basic Attack = Weapon Dmg (Hero stat) + Weapon Power (from items)
But as you might have guessed, armor matters here too. That’s why Catherine can be so darn hard to kill!
The actual damage a hero deals with their basic attack is called basic damage, and is calculated like this.
Basic Dmg = Basic Atk/(1 + (Enemy’s Armor/100))
All this is good and dandy if you like math, but let’s put this into practice with my favorite hero, Adagio ! Say you are at level 1 and you take a Weapon Blade to go shank that first creep by the tree (the one that gives you health when it dies). Here is how that pans out. Ready? Ok go!
Basic Attack = Adagio Weapon Dmg at level one (64) + Weapon Blade Weapon Pwr (15) = 79!
This is amazing work put together by BlueBadger. Go read the guide and join the conversation!