Bloodbat Summoner

Flying
At the beginning of combat on your turn, up to one target Blood token you control becomes a 2/2 black Bat creature with flying and haste in addition to its other types.

Voldaren Bloodcaster

Flying
Whenever this creature or another nontoken creature you control dies, create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this token: Draw a card.")
Whenever you create a Blood token, if you control five or more Blood tokens, transform this creature.

Voldaren Bloodcaster // Bloodbat Summoner

Blood Artist

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

Shilgengar, Sire of Famine

Flying
Sacrifice another creature: Create a Blood token. If you sacrificed an Angel this way, create a number of Blood tokens equal to its toughness instead.
{W/B}{W/B}{W/B}, Sacrifice six Blood tokens: Return each creature card from your graveyard to the battlefield with a finality counter on it. Those creatures are Vampires in addition to their other types.

Morbid Opportunist

Whenever one or more other creatures die, draw a card. This ability triggers only once each turn.

Nadier's Nightblade

Whenever a token you control leaves the battlefield, each opponent loses 1 life and you gain 1 life.

Grim Haruspex

Morph {B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
Whenever another nontoken creature you control dies, draw a card.

Fleshbag Marauder

When this creature enters, each player sacrifices a creature of their choice.

Vraan, Executioner Thane

Whenever one or more other creatures you control die, each opponent loses 2 life and you gain 2 life. This ability triggers only once each turn.

Accursed Marauder

When this creature enters, each player sacrifices a nontoken creature of their choice.

Moonstone Eulogist

Flying
Whenever a creature an opponent controls dies, you create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this token: Draw a card.")
Whenever you sacrifice an artifact, put a +1/+1 counter on this creature and you gain 1 life.

Cruel Celebrant

Whenever this creature or another creature or planeswalker you control dies, each opponent loses 1 life and you gain 1 life.

Woe Strider

When this creature enters, create a 0/1 white Goat creature token.
Sacrifice another creature: Scry 1.
Escape—{3}{B}{B}, Exile four other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)
This creature escapes with two +1/+1 counters on it.

Plaguecrafter

When this creature enters, each player sacrifices a creature or planeswalker of their choice. Each player who can't discards a card.

Vampire's Kiss

Target player loses 2 life and you gain 2 life. Create two Blood tokens. (They're artifacts with "{1}, {T}, Discard a card, Sacrifice this token: Draw a card.")

Carrion Feeder

This creature can't block.
Sacrifice a creature: Put a +1/+1 counter on this creature.

Pointed Discussion

You draw two cards, lose 2 life, then create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this token: Draw a card.")

Marionette Apprentice

Fabricate 1 (When this creature enters, put a +1/+1 counter on it or create a 1/1 colorless Servo artifact creature token.)
Whenever another creature or artifact you control is put into a graveyard from the battlefield, each opponent loses 1 life.

Karmic Guide

Flying, protection from black
Echo {3}{W}{W} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
When this creature enters, return target creature card from your graveyard to the battlefield.

Massacre Wurm

When this creature enters, creatures your opponents control get -2/-2 until end of turn.
Whenever a creature an opponent controls dies, that player loses 2 life.

Skyclave Apparition

When this creature enters, exile up to one target nonland, nontoken permanent you don't control with mana value 4 or less.
When this creature leaves the battlefield, the exiled card's owner creates an X/X blue Illusion creature token, where X is the mana value of the exiled card.

Thalisse, Reverent Medium

At the beginning of each end step, create X 1/1 white Spirit creature tokens with flying, where X is the number of tokens you created this turn.

Midnight Reaper

Whenever a nontoken creature you control dies, this creature deals 1 damage to you and you draw a card.

Kamber, the Plunderer

Partner with Laurine, the Diversion (When this creature enters, target player may put Laurine into their hand from their library, then shuffle.)
Lifelink
Whenever a creature an opponent controls dies, you gain 1 life and create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this token: Draw a card.")

Zulaport Cutthroat

Whenever this creature or another creature you control dies, each opponent loses 1 life and you gain 1 life.

Shriekmaw

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
When this creature enters, destroy target nonartifact, nonblack creature.
Evoke {1}{B} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Elas il-Kor, Sadistic Pilgrim

Deathtouch
Whenever another creature you control enters, you gain 1 life.
Whenever another creature you control dies, each opponent loses 1 life.

Falkenrath Forebear

Flying
This creature can't block.
Whenever this creature deals combat damage to a player, create a Blood token.
{B}, Sacrifice two Blood tokens: Return this card from your graveyard to the battlefield.

Merciless Executioner

Jadar, Ghoulcaller of Nephalia

At the beginning of your end step, if you control no creatures with decayed, create a 2/2 black Zombie creature token with decayed. (It can't block. When it attacks, sacrifice it at end of combat.)

Stitcher's Supplier

When this creature enters or dies, mill three cards. (Put the top three cards of your library into your graveyard.)

Bartolomé del Presidio

Sacrifice another creature or artifact: Put a +1/+1 counter on Bartolomé del Presidio.

Syr Konrad, the Grim

Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad deals 1 damage to each opponent.
{1}{B}: Each player mills a card. (They each put the top card of their library into their graveyard.)

Viscera Seer

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

Ophiomancer

At the beginning of each upkeep, if you control no Snakes, create a 1/1 black Snake creature token with deathtouch.

Demon's Disciple

When this creature enters, each player sacrifices a creature or planeswalker of their choice.

Grave Titan

Deathtouch
Whenever this creature enters or attacks, create two 2/2 black Zombie creature tokens.