Dark Impostor

{4}{B}{B}: Exile target creature and put a +1/+1 counter on Dark Impostor.
Dark Impostor has all activated abilities of all creature cards exiled with it.

Bloodlord of Vaasgoth

Bloodthirst 3 (If an opponent was dealt damage this turn, this creature enters with three +1/+1 counters on it.)
Flying
Whenever you cast a Vampire creature spell, it gains bloodthirst 3.

Anowon, the Ruin Sage

At the beginning of your upkeep, each player sacrifices a non-Vampire creature of their choice.

Edgar Markov

Eminence — Whenever you cast another Vampire spell, if Edgar Markov is in the command zone or on the battlefield, create a 1/1 black Vampire creature token.
First strike, haste
Whenever Edgar Markov attacks, put a +1/+1 counter on each Vampire you control.

Butcher of Malakir

Flying
Whenever Butcher of Malakir or another creature you control dies, each opponent sacrifices a creature of their choice.

Blood Artist

Whenever Blood Artist or another creature dies, target player loses 1 life and you gain 1 life.

Captivating Vampire

Other Vampire creatures you control get +1/+1.
Tap five untapped Vampires you control: Gain control of target creature. It becomes a Vampire in addition to its other types.

Bloodline Necromancer

Lifelink
When Bloodline Necromancer enters, you may return target Vampire or Wizard creature card from your graveyard to the battlefield.

Blood Baron of Vizkopa

Lifelink, protection from white and from black
As long as you have 30 or more life and an opponent has 10 or less life, Blood Baron of Vizkopa gets +6/+6 and has flying.

Bloodhusk Ritualist

Multikicker {B} (You may pay an additional {B} any number of times as you cast this spell.)
When Bloodhusk Ritualist enters, target opponent discards a card for each time it was kicked.

Bloodsworn Steward

Flying
Commander creatures you control get +2/+2 and have haste.

Crimson Honor Guard

Trample
At the beginning of each player's end step, Crimson Honor Guard deals 4 damage to that player unless they control a commander.