Weapon Defense vs. Damage Taken

It's not an easy one to figure out from ingame tests, a lot of things affect it
- monster atk
- player defense
- player str
- player class
- player level

Only 1 of these (defense) is easy to vary without affecting the rest, and there's no stat screen showing how much damage monsters do so the only way to find out is to keep bumping the monster until you've seen the highest and lowest damage it does, which takes longer and costs more than most other ingame formulas.


The trouble is also magnitude - only the monster atk has a noticeable effect (+130 monster atk = ~3k damage for Horntail) while the rest are tiny (+200 defense = ~90 damage difference, +1000 str = ~200 damage difference, +200 levels = ~200 difference again, and the classes affect how these numbers interact - a beginner's str barely changes the damage they take.)

Well...
I saw the other thread where Ruust found the Heal formula using some data from people testing. He found the formula without an actual number as the base damage.

When finding damage equations, we are given the monster's def and your own attack. Similarly, we are given the monster's attack and our own def. So in a sense, it shouldn't be harder to find the actual formula. It's just that nobody has tried. Why not try then?

I'm curious why the horntail pendant and the zakum helmet combined can give you nearly a 400 damage reduction. (Which goes against the hypothesis that 2.5 def = 1 damage taken off.)