Anowon, the Ruin Sage

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

Bishop of the Bloodstained

When Bishop of the Bloodstained enters, target opponent loses 1 life for each Vampire you control.

Bloodcrazed Socialite

Menace
When Bloodcrazed Socialite enters, create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")
Whenever Bloodcrazed Socialite attacks, you may sacrifice a Blood token. If you do, it gets +2/+2 until end of turn.

Callous Bloodmage

When Callous Bloodmage enters, choose one —
• Create a 1/1 black and green Pest creature token with "When this creature dies, you gain 1 life."
• You draw a card and you lose 1 life.
• Exile target player's graveyard.

Bat Whisperer

When Bat Whisperer enters, if an opponent lost life this turn, create a 1/1 black Bat creature token with flying.

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.

Timothar, Baron of Bats

Ward—Discard a card.
Whenever another nontoken Vampire you control dies, you may pay {1} and exile it. If you do, create a 1/1 black Bat creature token with flying. It gains "When this creature deals combat damage to a player, sacrifice it and return the exiled card to the battlefield tapped."

Arrogant Outlaw

When Arrogant Outlaw enters, if an opponent lost life this turn, each opponent loses 2 life and you gain 2 life.

Bloodtithe Collector

Flying
When Bloodtithe Collector enters, if an opponent lost life this turn, each opponent discards a card.