Hello everybody! In addition to the Countblood and Awakened Blood of Strahd's Chosen in Rise of the Vampires, I offer to you a new addition to your playable character options; the Vampiric Blood Sorcerer! With a focus on vampiric thematic features, this sorcerer has a way to gain temporary hit points as well as vampiric spells naturally (which are normally locked like Solarmancy or Atlantean Spells!)
You'll note that most of this sorcerous origin is about getting phat stacks of temporary hit points, and having some fun flavorful abilities that relate to gaining those hit points, like increasing your lifespan or reattaching limbs!