[1.2.253] Attack Belt

Still, though, magic damage should be calculated differently. When almost all of your damage is calculated off of a single number that increases at a constant rate, it barely increases proportionally at higher levels.

Spell Damage:
MAX = ((Magic²/1000 + Magic)/30 + INT/200) * Spell Attack
MIN = ((Magic²/1000 + Magic * Mastery * 0.9)/30 + INT/200) * Spell Attack

It is not a linear/constant rate. It's quadratic, only problem is that it's by such a low factor...