Why we don't have some sort of self heal that costs mana/blood escapes me, as we are a tank, after all, and our self-healing is by far the weakest, and yet we do not have the ability to convert this one resource into HP even though half of our job is converting blood into mana, mana into blood, or either into potency. Seems we should be able to convert at least one of those resources to HP.
I wondered the same, blood seems associated with life of vampirism at some point. I don"t get why spending blood does'nt restore us a portion of health (Something like, 5 or 10% of max HP for 50 blood spent). Delirium is also akin to fueling ourselves with a corrupted energy, as shown in the animation.