Harvester of Souls

Deathtouch
Whenever another nontoken creature dies, you may draw a card.

Withengar Unbound

Flying, intimidate, trample (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Whenever a player loses the game, put thirteen +1/+1 counters on Withengar Unbound.

Elbrus, the Binding Blade

Equipped creature gets +1/+0.
When equipped creature deals combat damage to a player, unattach Elbrus, the Binding Blade, then transform it.
Equip {1}

Elbrus, the Binding Blade // Withengar Unbound

Malicious Affliction

Morbid — When you cast this spell, if a creature died this turn, you may copy Malicious Affliction and may choose a new target for the copy.
Destroy target nonblack creature.

Stensia Uprising

At the beginning of your end step, create a 1/1 red Human creature token. Then if you control exactly thirteen permanents, you may sacrifice Stensia Uprising. When you do, it deals 7 damage to any target.

Rune-Scarred Demon

Flying
When Rune-Scarred Demon enters the battlefield, search your library for a card, put it into your hand, then shuffle.

Command Tower

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

Rakdos Guildgate

Rakdos Guildgate enters the battlefield tapped.
{T}: Add {B} or {R}.

Hidetsugu, Devouring Chaos

{B}, Sacrifice a creature: Scry 2.
{2}{R}, {T}: Exile the top card of your library. You may play that card this turn. When you exile a nonland card this way, Hidetsugu, Devouring Chaos deals damage equal to the exiled card's mana value to any target.

Master of the Feast

Flying
At the beginning of your upkeep, each opponent draws a card.

Sign in Blood

Target player draws two cards and loses 2 life.

Nexus of Becoming

At the beginning of combat on your turn, draw a card. Then you may exile an artifact or creature card from your hand. If you do, create a token that's a copy of the exiled card, except it's a 3/3 Golem artifact creature in addition to its other types.

Anger

Haste
As long as Anger is in your graveyard and you control a Mountain, creatures you control have haste.

Rakdos, the Showstopper

Flying, trample
When Rakdos, the Showstopper enters the battlefield, flip a coin for each creature that isn't a Demon, Devil, or Imp. Destroy each creature whose coin comes up tails.

Gibbering Fiend

When Gibbering Fiend enters the battlefield, it deals 1 damage to each opponent.
Delirium — At the beginning of each opponent's upkeep, if there are four or more card types among cards in your graveyard, Gibbering Fiend deals 1 damage to that player.

Crushing Disappointment

Each player loses 2 life. You draw two cards.

Cadaver Imp

Flying
When Cadaver Imp enters the battlefield, you may return target creature card from your graveyard to your hand.

Vexing Devil

When Vexing Devil enters the battlefield, any opponent may have it deal 4 damage to them. If a player does, sacrifice Vexing Devil.

Evolving Wilds

{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Taurean Mauler

Changeling (This card is every creature type.)
Whenever an opponent casts a spell, you may put a +1/+1 counter on Taurean Mauler.

Mayhem Devil

Whenever a player sacrifices a permanent, Mayhem Devil deals 1 damage to any target.

Terramorphic Expanse

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Embodiment of Agonies

Flying, deathtouch
Embodiment of Agonies enters the battlefield 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.)

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Kardur, Doomscourge

When Kardur, Doomscourge enters the battlefield, until your next turn, creatures your opponents control attack each combat if able and attack a player other than you if able.
Whenever an attacking creature dies, each opponent loses 1 life and you gain 1 life.

Bojuka Bog

Bojuka Bog enters the battlefield tapped.
When Bojuka Bog enters the battlefield, exile target player's graveyard.
{T}: Add {B}.

Chainer, Nightmare Adept

Discard a card: You may cast a creature spell from your graveyard this turn. Activate only once each turn.
Whenever a nontoken creature enters the battlefield under your control, if you didn't cast it from your hand, it gains haste until your next turn.

Diabolic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Goremand

As an additional cost to cast this spell, sacrifice a creature.
Flying
Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
When Goremand enters the battlefield, each opponent sacrifices a creature.

Sol Ring

Blood Speaker

At the beginning of your upkeep, you may sacrifice Blood Speaker. If you do, search your library for a Demon card, reveal that card, put it into your hand, then shuffle.
Whenever a Demon enters the battlefield under your control, return Blood Speaker from your graveyard to your hand.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Languish

All creatures get -4/-4 until end of turn.

Path of Ancestry

Path of Ancestry enters the battlefield tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Ash Barrens

{T}: Add {C}.
Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Rakdos Joins Up

When Rakdos Joins Up enters the battlefield, return target creature card from your graveyard to the battlefield with two additional +1/+1 counters on it.
Whenever a legendary creature you control dies, Rakdos Joins Up deals damage equal to that creature's power to target opponent.

Terminate

Destroy target creature. It can't be regenerated.

Raphael, Fiendish Savior

Flying
Other Demons, Devils, Imps, and Tieflings you control get +1/+1 and have lifelink.
At the beginning of each end step, if a creature card was put into your graveyard from anywhere this turn, create a 1/1 red Devil creature token with "When this creature dies, it deals 1 damage to any target."

Rakdos Charm

Choose one —
• Exile target player's graveyard.
• Destroy target artifact.
• Each creature deals 1 damage to its controller.

Akoum Refuge

Akoum Refuge enters the battlefield tapped.
When Akoum Refuge enters the battlefield, you gain 1 life.
{T}: Add {B} or {R}.

Mindwrack Demon

Flying, trample
When Mindwrack Demon enters the battlefield, mill four cards.
Delirium — At the beginning of your upkeep, you lose 4 life unless there are four or more card types among cards in your graveyard.

Demon of Dark Schemes

Flying
When Demon of Dark Schemes enters the battlefield, all other creatures get -2/-2 until end of turn.
Whenever another creature dies, you get {E} (an energy counter).
{2}{B}, Pay {E}{E}{E}{E}: Put target creature card from a graveyard onto the battlefield under your control tapped.

Victimize

Choose two target creature cards in your graveyard. Sacrifice a creature. If you do, return the chosen cards to the battlefield tapped.

Mark of the Oni

Enchant creature
You control enchanted creature.
At the beginning of the end step, if you control no Demons, sacrifice Mark of the Oni.

Riveteers Overlook

When Riveteers Overlook enters the battlefield, sacrifice it. When you do, search your library for a basic Swamp, Mountain, or Forest card, put it onto the battlefield tapped, then shuffle and you gain 1 life.

Arcane Signet

Vivid Crag

Vivid Crag enters the battlefield tapped with two charge counters on it.
{T}: Add {R}.
{T}, Remove a charge counter from Vivid Crag: Add one mana of any color.

Rakdos Carnarium

Rakdos Carnarium enters the battlefield tapped.
When Rakdos Carnarium enters the battlefield, return a land you control to its owner's hand.
{T}: Add {B}{R}.

Rocky Tar Pit

Rocky Tar Pit enters the battlefield tapped.
{T}, Sacrifice Rocky Tar Pit: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Theater of Horrors

At the beginning of your upkeep, exile the top card of your library.
During your turn, if an opponent lost life this turn, you may play lands and cast spells from among cards exiled with Theater of Horrors.
{3}{R}: Theater of Horrors deals 1 damage to target opponent or planeswalker.

Dragonskull Summit

Dragonskull Summit enters the battlefield tapped unless you control a Swamp or a Mountain.
{T}: Add {B} or {R}.

Dreadbore

Vampiric Rites

{1}{B}, Sacrifice a creature: You gain 1 life and draw a card.

Xathrid Demon

Flying, trample
At the beginning of your upkeep, sacrifice a creature other than Xathrid Demon, then each opponent loses life equal to the sacrificed creature's power. If you can't sacrifice a creature, tap Xathrid Demon and you lose 7 life.

Vivid Marsh

Vivid Marsh enters the battlefield tapped with two charge counters on it.
{T}: Add {B}.
{T}, Remove a charge counter from Vivid Marsh: Add one mana of any color.

The Balrog, Durin's Bane

This spell costs {1} less to cast for each permanent sacrificed this turn.
Haste
The Balrog, Durin's Bane can't be blocked except by legendary creatures.
When The Balrog dies, destroy target artifact or creature an opponent controls.

Demon of Wailing Agonies

Flying
Lieutenant — As long as you control your commander, Demon of Wailing Agonies gets +2/+2 and has "Whenever Demon of Wailing Agonies deals combat damage to a player, that player sacrifices a creature."

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Tibalt, Rakish Instigator

Your opponents can't gain life.
−2: Create a 1/1 red Devil creature token with "When this creature dies, it deals 1 damage to any target."

Foreboding Ruins

As Foreboding Ruins enters the battlefield, you may reveal a Swamp or Mountain card from your hand. If you don't, Foreboding Ruins enters the battlefield tapped.
{T}: Add {B} or {R}.

Blood Pact

Not Dead After All

Until end of turn, target creature you control gains "When this creature dies, return it to the battlefield tapped under its owner's control, then create a Wicked Role token attached to it." (Enchanted creature gets +1/+1. When this Aura is put into a graveyard, each opponent loses 1 life.)

Death-Rattle Oni

Flash
This spell costs {2} less to cast for each creature that died this turn.
When Death-Rattle Oni enters the battlefield, destroy all other creatures that were dealt damage this turn.

Shadowborn Demon

Flying
When Shadowborn Demon enters the battlefield, destroy target non-Demon creature.
At the beginning of your upkeep, if there are fewer than six creature cards in your graveyard, sacrifice a creature.

Swamp

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Demonlord Belzenlok

Flying, trample
When Demonlord Belzenlok enters the battlefield, 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.

Captive Audience

Captive Audience enters the battlefield under the control of an opponent of your choice.
At the beginning of your upkeep, choose one that hasn't been chosen —
• Your life total becomes 4.
• Discard your hand.
• Each opponent creates five 2/2 black Zombie creature tokens.

Koth of the Hammer

+1: Untap target Mountain. It becomes a 4/4 red Elemental creature until end of turn. It's still a land.
−2: Add {R} for each Mountain you control.
−5: You get an emblem with "Mountains you control have '{T}: This land deals 1 damage to any target.'"

Mountain

Bloodgift Demon

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

Rakdos Locket

{T}: Add {B} or {R}.
{B/R}{B/R}{B/R}{B/R}, {T}, Sacrifice Rakdos Locket: Draw two cards.

Temple of Malice

Temple of Malice enters the battlefield tapped.
When Temple of Malice enters the battlefield, scry 1.
{T}: Add {B} or {R}.

Dark Ritual

Rakdos Signet

Demon of Catastrophes

As an additional cost to cast this spell, sacrifice a creature.
Flying, trample

Painful Quandary

Whenever an opponent casts a spell, that player loses 5 life unless they discard a card.

Reaper from the Abyss

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

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice Hedron Archive: Draw two cards.

Tragic Slip

Target creature gets -1/-1 until end of turn.
Morbid — That creature gets -13/-13 until end of turn instead if a creature died this turn.

Smoldering Marsh

({T}: Add {B} or {R}.)
Smoldering Marsh enters the battlefield tapped unless you control two or more basic lands.

Indulgent Tormentor

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

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Spawn of Mayhem

Spectacle {1}{B}{B} (You may cast this spell for its spectacle cost rather than its mana cost if an opponent lost life this turn.)
Flying, trample
At the beginning of your upkeep, Spawn of Mayhem deals 1 damage to each player. Then if you have 10 or less life, put a +1/+1 counter on Spawn of Mayhem.

Bloodfell Caves

Bloodfell Caves enters the battlefield tapped.
When Bloodfell Caves enters the battlefield, you gain 1 life.
{T}: Add {B} or {R}.

Mimic Vat

Imprint — Whenever a nontoken creature dies, you may exile that card. If you do, return each other card exiled with Mimic Vat to its owner's graveyard.
{3}, {T}: Create a token that's a copy of a card exiled with Mimic Vat. It gains haste. Exile it at the beginning of the next end step.

Bedevil

Destroy target artifact, creature, or planeswalker.

Rakdos's Return

Rakdos's Return deals X damage to target opponent or planeswalker. That player or that planeswalker's controller discards X cards.