Dreadhorde Invasion

At the beginning of your upkeep, you lose 1 life and amass Zombies 1. (Put a +1/+1 counter on an Army you control. It's also a Zombie. If you don't control an Army, create a 0/0 black Zombie Army creature token first.)
Whenever a Zombie token you control with power 6 or greater attacks, it gains lifelink until end of turn.

Priest of Forgotten Gods

{T}, Sacrifice two other creatures: Any number of target players each lose 2 life and sacrifice a creature. You add {B}{B} and draw a card.

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, the Grim 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.)

Corpse Knight

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

Knight of the White Orchid

First strike
When Knight of the White Orchid enters, if an opponent controls more lands than you, you may search your library for a Plains card, put it onto the battlefield, then shuffle.

Open the Graves

Whenever a nontoken creature you control dies, create a 2/2 black Zombie creature token.

Eerie Interlude

Exile any number of target creatures you control. Return those cards to the battlefield under their owner's control at the beginning of the next end step.

Teysa, Orzhov Scion

Sacrifice three white creatures: Exile target creature.
Whenever another black creature you control dies, create a 1/1 white Spirit creature token with flying.

Flicker

Exile target nontoken permanent, then return it to the battlefield under its owner's control.

Angel of Despair

Flying
When Angel of Despair enters, destroy target permanent.

Burnished Hart

{3}, Sacrifice Burnished Hart: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Sunblast Angel

Flying
When Sunblast Angel enters, destroy all tapped creatures.

Pitiless Plunderer

Whenever another creature you control dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

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.

Utter End

Kaya's Wrath

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

Butcher of Malakir

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

Solemn Simulacrum

When Solemn Simulacrum enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Despark

Exile target permanent with mana value 4 or greater.

Ministrant of Obligation

Afterlife 2 (When this creature dies, create two 1/1 white and black Spirit creature tokens with flying.)

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Talisman of Hierarchy

{T}: Add {C}.
{T}: Add {W} or {B}. Talisman of Hierarchy deals 1 damage to you.

Flickerwisp

Flying
When Flickerwisp enters, exile another target permanent. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Pawn of Ulamog

Whenever Pawn of Ulamog or another nontoken creature you control dies, you may create a 0/1 colorless Eldrazi Spawn creature token. It has "Sacrifice this creature: Add {C}."

Reassembling Skeleton

{1}{B}: Return Reassembling Skeleton from your graveyard to the battlefield tapped.

Cruel Celebrant

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

Athreos, Shroud-Veiled

Indestructible
As long as your devotion to white and black is less than seven, Athreos isn't a creature.
At the beginning of your end step, put a coin counter on another target creature.
Whenever a creature with a coin counter on it dies or is put into exile, return that card to the battlefield under your control.

Archon of Justice

Flying
When Archon of Justice dies, exile target permanent.

Sun Titan

Vigilance
Whenever Sun Titan enters or attacks, you may return target permanent card with mana value 3 or less from your graveyard to the battlefield.

Revel in Riches

Whenever a creature an opponent controls dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
At the beginning of your upkeep, if you control ten or more Treasures, you win the game.

Merciless Eviction

Choose one —
• Exile all artifacts.
• Exile all creatures.
• Exile all enchantments.
• Exile all planeswalkers.

Mortify

Swords to Plowshares

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

Vindictive Vampire

Whenever another creature you control dies, Vindictive Vampire deals 1 damage to each opponent and you gain 1 life.

Emeria Shepherd

Flying
Landfall — Whenever a land you control enters, you may return target nonland permanent card from your graveyard to your hand. If that land is a Plains, you may return that nonland permanent card to the battlefield instead.

Aegis Angel

Flying (This creature can't be blocked except by creatures with flying or reach.)
When Aegis Angel enters, another target permanent gains indestructible for as long as you control Aegis Angel. (Effects that say "destroy" don't destroy it. A creature with indestructible can't be destroyed by damage.)

Carrion Feeder

Carrion Feeder can't block.
Sacrifice a creature: Put a +1/+1 counter on Carrion Feeder.