Ob Nixilis, Unshackled

Flying, trample
Whenever an opponent searches their library, that player sacrifices a creature of their choice and loses 10 life.
Whenever another creature dies, put a +1/+1 counter on Ob Nixilis, Unshackled.

Radiant Destiny

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
As Radiant Destiny enters, choose a creature type.
Creatures you control of the chosen type get +1/+1. As long as you have the city's blessing, they also have vigilance.

Woebringer Demon

Flying
At the beginning of each player's upkeep, that player sacrifices a creature of their choice. If the player can't, sacrifice Woebringer Demon.

Doom Whisperer

Flying, trample
Pay 2 life: Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Razaketh, the Foulblooded

Flying, trample
Pay 2 life, Sacrifice another creature: Search your library for a card, put that card into your hand, then shuffle.

Liliana's Contract

When Liliana's Contract enters, you draw four cards and you lose 4 life.
At the beginning of your upkeep, if you control four or more Demons with different names, you win the game.

Bloodgift Demon

Flying
At the beginning of your upkeep, target player draws a card and loses 1 life.

Mirror Entity

Changeling (This card is every creature type.)
{X}: Until end of turn, creatures you control have base power and toughness X/X and gain all creature types.

Harvester of Souls

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever another nontoken creature dies, you may draw a card.

Birthing Boughs

{4}, {T}: Create a 2/2 colorless Shapeshifter creature token with changeling. (It has every creature type.)

Rune-Scarred Demon

Flying
When this creature enters, search your library for a card, put it into your hand, then shuffle.

Herald of Torment

Bestow {3}{B}{B} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Flying
At the beginning of your upkeep, you lose 1 life.
Enchanted creature gets +3/+3 and has flying.

Archfiend of Depravity

Flying
At the beginning of each opponent's end step, that player chooses up to two creatures they control, then sacrifices the rest.

Ob Nixilis, the Fallen

Landfall — Whenever a land you control enters, you may have target player lose 3 life. If you do, put three +1/+1 counters on Ob Nixilis, the Fallen.

Ayli, Eternal Pilgrim

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
{1}, Sacrifice another creature: You gain life equal to the sacrificed creature's toughness.
{1}{W}{B}, Sacrifice another creature: Exile target nonland permanent. Activate only if you have at least 10 life more than your starting life total.

Crib Swap

Changeling (This card is every creature type.)
Exile target creature. Its controller creates a 1/1 colorless Shapeshifter creature token with changeling.

Conspiracy

As Conspiracy enters, choose a creature type.
Creatures you control are the chosen type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.

Felidar Sovereign

Vigilance (Attacking doesn't cause this creature to tap.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)
At the beginning of your upkeep, if you have 40 or more life, you win the game.

Sower of Discord

Flying
As Sower of Discord enters, choose two players.
Whenever damage is dealt to one of the chosen players, the other chosen player also loses that much life.

Kagemaro, First to Suffer

Kagemaro, First to Suffer's power and toughness are each equal to the number of cards in your hand.
{B}, Sacrifice Kagemaro: All creatures get -X/-X until end of turn, where X is the number of cards in your hand.

Nameless Inversion

Changeling (This card is every creature type.)
Target creature gets +3/-3 and loses all creature types until end of turn.

Icon of Ancestry

As Icon of Ancestry enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
{3}, {T}: Look at the top three cards of your library. You may reveal a creature card of the chosen type from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Nefarox, Overlord of Grixis

Flying
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
Whenever Nefarox, Overlord of Grixis attacks alone, defending player sacrifices a creature of their choice.

Reiver Demon

Flying
When Reiver Demon enters, if you cast it from your hand, destroy all nonartifact, nonblack creatures. They can't be regenerated.

Kindred Dominance

Choose a creature type. Destroy all creatures that aren't of the chosen type.

Herald of Anguish

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Flying
At the beginning of your end step, each opponent discards a card.
{1}{B}, Sacrifice an artifact: Target creature gets -2/-2 until end of turn.

Indulgent Tormentor

Flying
At the beginning of your upkeep, draw a card unless target opponent sacrifices a creature of their choice or pays 3 life.

Ormendahl, Profane Prince

Westvale Abbey

{T}: Add {C}.
{5}, {T}, Pay 1 life: Create a 1/1 white and black Human Cleric creature token.
{5}, {T}, Sacrifice five creatures: Transform Westvale Abbey, then untap it.

Westvale Abbey // Ormendahl, Profane Prince

Embodiment of Agonies

Flying, deathtouch
Embodiment of Agonies enters with a +1/+1 counter on it for each different mana cost among nonland cards in your graveyard. (For example, {2}{B} and {1}{B}{B} are different mana costs.)

Reaper from the Abyss

Flying
Morbid — At the beginning of each end step, if a creature died this turn, destroy target non-Demon creature.

Demonlord Belzenlok

Flying, trample
When Demonlord Belzenlok enters, exile cards from the top of your library until you exile a nonland card, then put that card into your hand. If the card's mana value is 4 or greater, repeat this process. Demonlord Belzenlok deals 1 damage to you for each card put into your hand this way.

Vanquisher's Banner

As Vanquisher's Banner enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

Graveshifter

Changeling (This card is every creature type.)
When Graveshifter enters, you may return target creature card from your graveyard to your hand.

Test of Endurance

At the beginning of your upkeep, if you have 50 or more life, you win the game.

Pestilence Demon

Flying
{B}: Pestilence Demon deals 1 damage to each creature and each player.

Lord of the Void

Flying
Whenever Lord of the Void deals combat damage to a player, exile the top seven cards of that player's library, then put a creature card from among them onto the battlefield under your control.

Kothophed, Soul Hoarder

Flying
Whenever a permanent owned by another player is put into a graveyard from the battlefield, you draw a card and you lose 1 life.

Herald's Horn

As Herald's Horn enters, choose a creature type.
Creature spells you cast of the chosen type cost {1} less to cast.
At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

Vilis, Broker of Blood

Flying
{B}, Pay 2 life: Target creature gets -1/-1 until end of turn.
Whenever you lose life, draw that many cards. (Damage causes loss of life.)