Mark of the Vampiric Familiar

You have gained the Mark of Vampiric Familiar. You are now a Familiar to the vampire that bestowed the mark on you. While this mark is attached to your body you gain resistance to necrotic damage, immunity to the charmed condition, and the following effects: 

Vampiric Connection. While the familiar and its vampire master are on the same plane of existence, the vampire can communicate with the familiar telepathically, and the vampire can perceive through the familiar’s senses.

Deathless Agility.  The familiar takes the Dash or Disengage action as a bonus action.

 A vampire familiar loses its supernatural abilities and returns to its original Humanoid state if its vampire master relieves them of their service or is destroyed.