This is a really newbie question. But I've just never personally tested this and have grown kind of a unnatural disdain for this ability due to my ignorance/laziness.

Bloodbath, I know it heals for a % of your damage. But based on the tooltip I've always interpreted it as the % it heals is actually TAKEN AWAY from your damage.

For example, lets say you did 100 damage with ability x. When ability x is used while Bloodbath is up, you receive 25hp as heals and the damage you actually do is 100-25 = 75.

Please tell me I am wrong as it seems to be the case haha