Iv been testing out a pure blood build with all healing spells, and i think it's actually doing alot of damage. it sucks that you cant really see how much you're doing.
all you need to do is circle around the enemy and just spam it, then run to the side and heal. For an idea on how much damage it's doing It takes 3 casts(hold) to kill one of those fat ghoul things in the cerberus battle with 4 party group. (i do use +50% dmg -25%def sigil)--- When usually it takes Snowtree rootx2(freeze) Spear fragmentx1(critical explode) then another snowtree rootx2(freeze) Spear fragmentx1(critical explode) to kill it.
The regenesis seed isnt enough healing to outdo the damage, but it does help. you still need to go off to the side and do a healing bloom every now and then.
Also try not to get hit at all, because thatll set you back ALOT cause ull need to run off again and heal
btw This is my usual cerberus setup 
Btw i recommend going back to that single player quest when u need to kill that lady companion boss, and farm the stoneaxe edge spell for the cerberus battle (you need legendary rank to get it and u need barely unscathed bonus OR unscathed AND quick quest to get legendary ranking)
also guys id highly recommend the spell "stormbird pinion" (cerberus reward) what it does is it like makes you into a rocket and you repeatedly fly into the enemy (3times per 1 cast) doing damage, it actually does alot of damage based off the description. BUT that's not the reason i actually use it, i use it as a evasion move. basically when you cast it you become invulnerable for like 6 seconds (it sometimes(5%) buggs and you get hit from the charge move) but its really great for the cerberus move where he stabs the sword into the ground, just before he gets the spell off use the spell on him and it'll miss you 100% guaranteed.
