You are resistant to necrotic damage, but vulnerable against radiant damage.

You must drink 500ml of fresh blood per day or take 1d10 damage when the day ends.
Drinking blood restores 1d8 hit points.

To drink from an unwilling creature you must use the bite action.

You can drink from a willing creature without penalty. The creature will take 1d8 piercing damage and you gain the equivalent in hit points.

Half-Vampires are immortal, frozen at the age on which they were cursed. They do not age via natural or supernatural means.

When you are reduced to 0 hit points but not killed outright, you can drop to 1 hit point instead. You can’t use this feature again until you finish a long rest.

Thanks to your vampiric blood, you have superior vision in dark and dim conditions. You can see in dim light within 60 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 gray.

Your vampiric side gives you razor-sharp teeth you can use as a natural weapon for 1d8 plus your Strength modifier in place of an unarmed strike. On a successful hit you gain hit points equal to the damage you dealt.

This can be done once per long rest.

Upon a miss this action is not used up, and can be repeated until a successful bite attack has been made.

A willing participant does not use up the once per long rest use.

Half-vampires inherit a tendency toward chaos due to their inherent need to feed and are not strongly inclined toward good. 

However some exceptions have been known. A half-vampire may only choose to feed on animals, willing subjects or even bottled blood.

Half-vampires are the same size as an average human. Your  size is medium.

Your Strength score increases by 1, and your Constitution score increases by 2.

Sunlight is fatal to you, if immersed in this you will be destroyed and turn to dust. You cannot be revived.

if partially immersed in sunlight you take 1d20 damage per minute.

You can use your action to temporarily transform into a bat. For up to 10 minutes you assume the form and stats of a bat, you cannot cast spells, talk, or attack with anything except your bite. When you are reduced to 0 hit points while in bat form you automatically revert to your normal state.

After using this ability you must undergo a short or long rest before you can use it again.

Your base walking speed is 30 feet.

You can speak, read, and write Common and Infernal.