A vampire needs to drink blood after every long rest. Whenever you drink blood you gain temporary hitpoints equal to half your level rounded up.

If the vampire does not drink once before its next long rest its senses will enhance and it has advantage to all Perception checks. When in this state of enhanced senses the eyes turn blood red and you are blinded in sunlight. You may end the blinded condition caused by this feature as a bonus action for 10 minutes, when you do you take 2d8 radiant damage.

Each day you have not drunk any blood you may roll a d20. If you roll a natural 20 you enter a blood rage. until you drink blood you cannot regain hitpoints by resting. however, in this state you gain the following traits: Necrotic damage immunity, advantage on all attack rolls and a flying speed equal to your walking speed as blood red wings sprout from the back of the vampire. Additionally whenever you cast a spell in this blood rage state you regain hitpoints equal to the spells level.

Vampires have acces to ancient vampiric magic.  If you are a spellcaster you may cast the following spells once per short rest.

Polymorph targeting yourself only and using the following forms to choose from:spider, cat, bat or rat. While polymorphed in this way your Intelligence remains the same as before the transformation.

Charm Person

Command

 The save DC for these spells is 15.

Your Intelligence score increases by 2, your Constitution score increases by 1 and your Charisma score increases by 1.

vampires don't age. 

Charnel vampire tend towards maintaining the balance of life and death and if they perform their duties well they are of a lawful neutral alignment.

Angmar is Small.

Your base walking speed is 25 feet.

Accustomed to the night, you have superior vision in dark and dim conditions. You can see in dim light within 120 feet of you as if it were bright light, and in darkness as if it were dim light. You can’t discern color in darkness, only shades of red. While in direct sunlight, the vampire has disadvantage on Attack rolls.

You have advantage on all Intelligence, Wisdom, and Charisma saving throws against magic.

You can speak, read, and write Common and Gnomish. The Gnomish language, which uses the Dwarvish script, is renowned for its technical treatises and its catalogs of knowledge about the natural world.