Yeah i have one in the last days about magic mods, but more exactly magic damage.
I don't like lie, i'm take this from the "parma magica" of ars magica TTRPG.
this mod allows a little "ritual" that give a magic resistance, this is a %, how to work is based in the Parma type, you need wait a 1 in game hour for every ritual, you can only have one parma in your character and overrides other magic resistances from other sources.
-Blasting Parma: this parma give a 70% of magic resiatance(don't stack with resistance) every magic attack reduce the efficiency of the Blasting parma in 10%. the blasting parma takes 5 sec in restore and can't go below of 10%.
-Parma fabulosa: this parma give the half of the armor value(rounded down) has a magic resistance, this is a enchant made with the ritual and not compatible with protection related enchants and other parmas.
-Feint parma: this parma have 20% of chance to null the magic damage, if you have a low armor value they increases the parma chance of null the magic damage up 60%
-Prometheus parma: this parma give you a 30% of magic damage reduction, but if you have less than 10 hearts, every half heart add 5% of magic resistance. if you have more than 20 hearts every aditional heart decreases the value of prometheus parma by 5%