Murder

Vito, Thorn of the Dusk Rose

Whenever you gain life, target opponent loses that much life.
{3}{B}{B}: Creatures you control gain lifelink until end of turn.

Sengir Vampire

Flying (This creature can't be blocked except by creatures with flying or reach.)
Whenever a creature dealt damage by Sengir Vampire this turn dies, put a +1/+1 counter on Sengir Vampire.

Butcher of Malakir

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

Macabre Waltz

Return up to two target creature cards from your graveyard to your hand, then discard a card.

Swamp

Indulgent Aristocrat

Lifelink
{2}, Sacrifice a creature: Put a +1/+1 counter on each Vampire you control.

Blood Seeker

Whenever a creature an opponent controls enters, you may have that player lose 1 life.

Warlock Class

(Gain the next level as a sorcery to add its ability.)
At the beginning of your end step, if a creature died this turn, each opponent loses 1 life.
{1}{B}: Level 2
When this Class becomes level 2, look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.
{6}{B}: Level 3
At the beginning of your end step, each opponent loses life equal to the life they lost this turn. (Damage causes loss of life.)

Drana, Liberator of Malakir

Flying, first strike
Whenever Drana, Liberator of Malakir deals combat damage to a player, put a +1/+1 counter on each attacking creature you control.

Vampire Nighthawk

Vampire Hexmage

First strike
Sacrifice Vampire Hexmage: Remove all counters from target permanent.

Pulse Tracker

Whenever Pulse Tracker attacks, each opponent loses 1 life.

Defiant Bloodlord

Flying
Whenever you gain life, target opponent loses that much life.

Despise

Target opponent reveals their hand. You choose a creature or planeswalker card from it. That player discards that card.

Bloodthrone Vampire

Sacrifice a creature: Bloodthrone Vampire gets +2/+2 until end of turn.

Bloodbond Vampire

Whenever you gain life, put a +1/+1 counter on Bloodbond Vampire.

Drana, Kalastria Bloodchief

Flying
{X}{B}{B}: Target creature gets -0/-X until end of turn and Drana, Kalastria Bloodchief gets +X/+0 until end of turn.

Bloodchief Ascension

At the beginning of each end step, if an opponent lost 2 or more life this turn, you may put a quest counter on Bloodchief Ascension. (Damage causes loss of life.)
Whenever a card is put into an opponent's graveyard from anywhere, if Bloodchief Ascension has three or more quest counters on it, you may have that player lose 2 life. If you do, you gain 2 life.

Diabolic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Obelisk of Urd

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
As Obelisk of Urd enters, choose a creature type.
Creatures you control of the chosen type get +2/+2.

Child of Night

Guul Draz Assassin

Level up {1}{B} ({1}{B}: Put a level counter on this. Level up only as a sorcery.)
LEVEL 2-3
2/2
{B}, {T}: Target creature gets -2/-2 until end of turn.
LEVEL 4+
4/4
{B}, {T}: Target creature gets -4/-4 until end of turn.

Viscera Seer

Sacrifice a creature: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Sol Ring

Feast of Blood

Cast this spell only if you control two or more Vampires.
Destroy target creature. You gain 4 life.