Mirkwood Bats

Flying
Whenever you create or sacrifice a token, each opponent loses 1 life.

Carmen, Cruel Skymarcher

Flying
Whenever a player sacrifices a permanent, put a +1/+1 counter on Carmen, Cruel Skymarcher and you gain 1 life.
Whenever Carmen attacks, return up to one target permanent card with mana value less than or equal to Carmen's power from your graveyard to the battlefield.

Master of Dark Rites

{T}, Sacrifice another creature: Add {B}{B}{B}. Spend this mana only to cast Vampire, Cleric, and/or Demon spells.

Kaya's Wrath

Destroy all creatures. You gain life equal to the number of creatures you controlled that were destroyed this way.

Blood Artist

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

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Unearth

Return target creature card with mana value 3 or less from your graveyard to the battlefield.
Cycling {2} ({2}, Discard this card: Draw a card.)

Teysa Karlov

If a creature dying causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.
Creature tokens you control have vigilance and lifelink.

Sanguine Bond

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

Alms of the Vein

Target opponent loses 3 life and you gain 3 life.
Madness {B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Baron Bertram Graywater

Whenever one or more tokens you control enter, create a 1/1 black Vampire Rogue creature token with lifelink. This ability triggers only once each turn.
{1}{B}, Sacrifice another creature or artifact: Draw a card.

Acolyte of Aclazotz

{T}, Sacrifice another creature or artifact: Each opponent loses 1 life and you gain 1 life.

Fleshtaker

Whenever you sacrifice another creature, you gain 1 life and scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{1}, Sacrifice another creature: Fleshtaker gets +2/+2 until end of turn.

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.

Emergency Weld

Return target artifact or creature card from your graveyard to your hand. Create a 1/1 colorless Soldier artifact creature token.

Fanatical Offering

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Map token. (It's an artifact with "{1}, {T}, Sacrifice this artifact: Target creature you control explores. Activate only as a sorcery.")

Cruel Celebrant

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