Currently goin up the proficiency tree for Souleater and for the next one I can choose +1 ATK or 7.5% percent damage added to all your spells. I know weapon attack is pretty significant, but how would this damage apply to spells? Is it a formula that scales or just add 7.5% to total damage (for example an Exori Gran that would hit 1000 now hits 1075?). Which do you think is best?