Blessed Child, Wretched Child

Your vampiric lineage bubbles to the surface, mixing and meshing with your less monstrous sensibilities, providing you with the following benefits and abilities:

• Increase your Constitution, Dexterity, or Charisma score by 1, to a maximum of 20
• Dhampir's Rending Mastication. Your vampiric lineage claws at your soul, granting you an improved bite that grows stronger as you master more of the monster within. As a bonus action, you can bite. Your bite now deals 1d8 piercing damage. This bite's damage increases by 1d8 at 5th level (2d8), 9th level (3d8), 13th level (4d8), and 17th level (5d8). At level 20, the damage die becomes a d10. Attacks you make with this bite are made with your Dexterity modifier instead of Constitution modifier and you make attacks with advantage when at or below half of your hitpoints.
• Burgeoning Bloodline. Starting at level 5, your mastery over the monster increases. Choose a bloodline to represent the clan of your vampiric parent. Based on the bloodline you chose, you gain the following effects:
  • Baobhan Sith: You can expend a charge to change your bite damage to psychic. If the target is a creature, it must succeed on a Wisdom saving throw, or become charmed by you until the start of your next turn or until you or your companions do anything harmful to it.
  • Draugr: You can expend a charge to change your bite damage to necrotic. If the target is a creature, it must succeed on a Constitution saving throw, or have its hit point maximum reduced by the damage dealt whilst you gain temporary hitpoints equal to the damage dealt.
  • Camazotz: You can expend one charge to change your bite damage to acid. If the target is a creature, it must succeed on a Constitution saving throw, or become poisoned. A creature poisoned this way will take 2d4 poison damage until they are cured or succeed on a Constitution saving throw, which they can make at the start of each of their turns.
  • Candileja: You can expend one charge to change your bite damage to fire. If the target is a creature, it must succeed on a Strength saving throw or be restrained by chains of fire. While restrained, the target takes 2d4 fire damage at the end of its turn. The target can attempt the save again on the start of each of its turns.
  • Yuki-onna: You can expend one charge to change your bite damage to cold. If the target is a creature, it must succeed on a Constitution saving throw, or its speed is reduced to 0 and it cannot take reactions until the start of your next turn.
  • Impundulu: You can expend one charge to change your bite damage to thunder. If the target is a creature, it must succeed on a Dexterity saving throw, or it has disadvantage on attack rolls against you until the start of your next turn.

The saving throw DC for these effects equals 8 + your proficiency bonus + your Dexterity or Constitution modifier.

You can use this feat a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.