Blood curse

In the Legacy of Kain series vampirism is the result of a curse placed upon Janos Audron's race of vampires (which are angelic-looking & blue-skinned) cast by the Hylden; a race of beings who have small pteradon-like wings from their upper back (their descendents from the Blood Omen 2 are wingless), w/ grayish-green skin, different head crests depending on their individual genetic structures, & have 4 digits (while natural born vampires & adult turned vampires have 3 digits). The curse of vampirism imprisons the soul of the vampire in the flesh (immortality in a sense), requires the need for blood-mainly, sterility{can't (a)sexually reproduce}, & allows the vampire to develop inhuman abilities called Dark Gifts]] which develop differently in most normal vampires. Vampires can develop multiple dark gifts on their own &/or they can steal the dark gifts of other vampires (a living vampire like Kain must kill & absorb the deceased vampires veins in order to take & use the deceased vampires' dark gift. However in Raziel's case since he is a wraith who sill retains some of his vampiric qualities/revived vampire/vampire wraith & feeds on souls he must feed on the souls of vampires, humans, Hylden, eta (assuming it's a giant or powerful soul, or a numerous amount of souls like those of his brothers, the priestess, & the numerous Hylden souls possessing Turel in order for Raziel to be enhanced or influenced {the same applies for Raziel's wraith-blade except for the fact that it can accept energy overall not just souls as seen in Legacy of Kain: Soul Reaver 2}).Kain's first generation of descendents which are Raziel, Turel, Dumah, Rahab, Zephon, & Melchiah inherited most of their dark gifts from Kain... just in different versions. The children of Kain's 'sons' inherit most of the vampiric gifts from their patriarch but overall do not develop their own dark gifts (however the Melchiahim developed the habit of digging & popping up to attack enemies, & the Zephonim can spin webs).