Origins: Vampire

Origins: Vampire brings 2 origins to the game : Vampire and Vampire Lord.

Only the Vampire origin is selectable when choosing your origin. You'll need to drink the blood of the Ender Dragon to become a Vampire Lord, but it will not let you sip it without a fight.

(Until v2.0.0) You'll need to obtain the advancement "Free the End" to evolve from a Vampire to a Vampire Lord

Vampire

Undead :

Vampires are undead creatures that suck the blood of the living to fulfill their thirst.
Their undead condition makes them immune to poison and freezing damage, but weak to fire, and sunlight. They also don't have to breath to survive.

Unholy :

They are weak to wooden tools, as such being hit by one will incapacitate him for a brief amount of time.

Diet :

As vampires, their diet is limited to blood. They can suck it straight from the living or bottle it to drink later.
When their thirst is satisfied, vampires are stronger and faster than humans, and can see clearly in the dark.

Healing :

Vampires heal faster but it makes them thirsty quickly.
Their weakness to fire and sunlight prevents them from healing while affected by this.

Bat form :

Vampires can transform into bats to move discretly and prevent the sunlight from affecting them.
On the other hand this form is more fragile, and does not have hands, preventing them to use their tools.