Vampire Spawn

You have embraced your vampirism, unlocking ever more and greater dark gifts. Your bite damage increases to 1d8, a creature affected by your Charming Gaze remains charmed for a number of hours equal to your level, and you regain the use of Charming Gaze when you finish a short or long rest . 

You also gain the Spider Climb and Vampiric Regeneration features.

Spider Climb. You gain a climb speed equal to your Speed, and you can climb even on difficult surfaces and upside down on ceilings.

Vampiric Regeneration. Whenever you start your turn with at least 1 hit point and you haven't taken radiant damage or entered direct sunlight since the end of your last turn, you gain a number of temporary hit points equal to twice your proficiency bonus.

The price for your vampirism becomes all the greater. When you end your turn in contact with running water, you take 20 radiant damage.