Reiver Demon

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

Shadow-Rite Priest

Other Clerics you control get +1/+1.
{3}{B}{B}, {T}, Sacrifice another Cleric: Search your library for a black creature card, put it onto the battlefield, then shuffle.

Burning-Rune Demon

Flying
When Burning-Rune Demon enters, you may search your library for exactly two cards not named Burning-Rune Demon that have different names. If you do, reveal those cards. An opponent chooses one of them. Put the chosen card into your hand and the other into your graveyard, then shuffle.

Thrumming Stone

Spells you cast have ripple 4. (Whenever you cast a spell, you may reveal the top four cards of your library. You may cast spells with the same name as that spell from among the revealed cards without paying their mana costs. Put the rest on the bottom of your library.)

Lagomos, Hand of Hatred

At the beginning of combat on your turn, create a 2/1 red Elemental creature token with trample and haste. Sacrifice it at the beginning of the next end step.
{T}: Search your library for a card, put it into your hand, then shuffle. Activate only if five or more creatures died this turn.

Overseer of the Damned

Flying
When Overseer of the Damned enters, you may destroy target creature.
Whenever a nontoken creature an opponent controls dies, create a tapped 2/2 black Zombie creature token.

Getting

Bloodbond March

Whenever a player casts a creature spell, each player returns all cards with the same name as that spell from their graveyard to the battlefield.

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.

Shirei, Shizo's Caretaker

Whenever a creature with power 1 or less is put into your graveyard from the battlefield, you may return that card to the battlefield at the beginning of the next end step if Shirei, Shizo's Caretaker is still on the battlefield.

Rotlung Reanimator

Whenever Rotlung Reanimator or another Cleric dies, create a 2/2 black Zombie creature token.

Village Rites

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Skullclamp

Equipped creature gets +1/-1.
Whenever equipped creature dies, draw two cards.
Equip {1}

Woodland Chasm

({T}: Add {B} or {G}.)
Woodland Chasm enters tapped.

Bloodstained Mire

{T}, Pay 1 life, Sacrifice Bloodstained Mire: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Sign in Blood

Target player draws two cards and loses 2 life.

Reaper from the Abyss

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

Savage Lands

Savage Lands enters tapped.
{T}: Add {B}, {R}, or {G}.

Sulfurous Mire

({T}: Add {B} or {R}.)
Sulfurous Mire enters tapped.

Xathrid Necromancer

Whenever Xathrid Necromancer or another Human creature you control dies, create a tapped 2/2 black Zombie creature token.

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.

Dream Devourer

Each nonland card in your hand without foretell has foretell. Its foretell cost is equal to its mana cost reduced by {2}. (During your turn, you may pay {2} and exile it from your hand face down. Cast it on a later turn for its foretell cost.)
Whenever you foretell a card, Dream Devourer gets +2/+0 until end of turn.

Sek'Kuar, Deathkeeper

Whenever another nontoken creature you control dies, create a 3/1 black and red Graveborn creature token with haste.

Bloodgift Demon

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

Verdant Catacombs

{T}, Pay 1 life, Sacrifice Verdant Catacombs: Search your library for a Swamp or Forest card, put it onto the battlefield, then shuffle.

Infernal Sovereign

Flying, trample
Skip your draw step.
Whenever you play a land or cast a spell, you draw a card and you lose 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.

Viscera Seer

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

Dead of Winter

All nonsnow creatures get -X/-X until end of turn, where X is the number of snow permanents you control.

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Echoing Return

Return target creature card and all other cards with the same name as that card from your graveyard to your hand.

Lightning Coils

Whenever a nontoken creature you control dies, put a charge counter on Lightning Coils.
At the beginning of your upkeep, if Lightning Coils has five or more charge counters on it, remove all of them from it and create that many 3/1 red Elemental creature tokens with haste. Exile them at the beginning of the next end step.

Taborax, Hope's Demise

Flying
Taborax, Hope's Demise has lifelink as long as it has five or more +1/+1 counters on it.
Whenever another nontoken creature you control dies, put a +1/+1 counter on Taborax. If that creature was a Cleric, you may draw a card. If you do, you lose 1 life.

Wooded Foothills

{T}, Pay 1 life, Sacrifice Wooded Foothills: Search your library for a Mountain or Forest card, put it onto the battlefield, then shuffle.

Karplusan Forest

{T}: Add {C}.
{T}: Add {R} or {G}. Karplusan Forest deals 1 damage to you.

Llanowar Wastes

{T}: Add {C}.
{T}: Add {B} or {G}. Llanowar Wastes deals 1 damage to you.

Necropotence

Skip your draw step.
Whenever you discard a card, exile that card from your graveyard.
Pay 1 life: Exile the top card of your library face down. Put that card into your hand at the beginning of your next end step.

Snow-Covered Swamp

Ad Nauseam

Reveal the top card of your library and put that card into your hand. You lose life equal to its mana value. You may repeat this process any number of times.

Rune-Scarred Demon

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

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.

Have

Shadowborn Apostle

A deck can have any number of cards named Shadowborn Apostle.
{B}, Sacrifice six creatures named Shadowborn Apostle: Search your library for a Demon creature card, put it onto the battlefield, then shuffle.

Infernal Grasp

Destroy target creature. You lose 2 life.

Highland Forest

({T}: Add {R} or {G}.)
Highland Forest enters tapped.

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.)

Sulfurous Springs

{T}: Add {C}.
{T}: Add {B} or {R}. Sulfurous Springs deals 1 damage to you.