Damage taken = Int {Enemy ATK
* (1 + Enemy ATK Buffs)
* (Enemy Elemental Advantage + Elemental Buff)
* (1 - Ally Reduce DMG)
/ (Ally DEF(10) + Soul DEF / 10)
/ (1 + Assist DEF + Ability DEF + Accessory DEF)
* (1 + DMG Range)}
* DMG Multiplier
It's 0,75 in this case. It's still additive with any elemental buff the enemy can have.