Molten Monstrosity

This spell costs {X} less to cast, where X is the greatest power among creatures you control.
Trample

Subversion

At the beginning of your upkeep, each opponent loses 1 life. You gain life equal to the life lost this way.

Thriving Moor

This land enters tapped. As it enters, choose a color other than black.
{T}: Add {B} or one mana of the chosen color.

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.

Spinerock Knoll

Hideaway 4 (When this land enters, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)
This land enters tapped.
{T}: Add {R}.
{R}, {T}: You may play the exiled card without paying its mana cost if an opponent was dealt 7 or more damage this turn.

Champion's Helm

Equipped creature gets +2/+2.
As long as equipped creature is legendary, it has hexproof. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Swamp

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Rune-Scarred Demon

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

Sweeping Cleave

Target creature you control gains double strike until end of turn. (Then exile this card. You may cast the artifact later from exile.)

Two-Handed Axe

Whenever equipped creature attacks, double its power until end of turn.
Equip {1}{R}

Two-Handed Axe // Sweeping Cleave

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.

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.

Glorybringer

Flying, haste
You may exert this creature as it attacks. When you do, it deals 4 damage to target non-Dragon creature an opponent controls. (An exerted creature won't untap during your next untap step.)

Sower of Discord

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

Command Tower

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

Prophetic Prism

When this artifact enters, draw a card.
{1}, {T}: Add one mana of any color.

Dragonskull Summit

This land enters tapped unless you control a Swamp or a Mountain.
{T}: Add {B} or {R}.

Phyrexian Reclamation

{1}{B}, Pay 2 life: Return target creature card from your graveyard to your hand.

Meteor Golem

When this creature enters, destroy target nonland permanent an opponent controls.

Hero's Downfall

Final Parting

Search your library for two cards. Put one into your hand and the other into your graveyard. Then shuffle.

Rakdos Keyrune

{T}: Add {B} or {R}.
{B}{R}: This artifact becomes a 3/1 black and red Devil artifact creature with first strike until end of turn.

Vedalken Orrery

You may cast spells as though they had flash.

Mountain

Lightning-Rig Crew

{T}: This creature deals 1 damage to each opponent.
Whenever you cast a Pirate spell, untap this creature.

Smoldering Marsh

({T}: Add {B} or {R}.)
This land enters tapped unless you control two or more basic lands.

Empyrial Plate

Equipped creature gets +1/+1 for each card in your hand.
Equip {2}

Rakdos, the Showstopper

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

In Thrall to the Pit

Kicker {2}{B} (You may pay an additional {2}{B} as you cast this spell.)
Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. If this spell was kicked, sacrifice that creature at the beginning of the next end step.

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, this creature deals 1 damage to each player. Then if you have 10 or less life, put a +1/+1 counter on this creature.

Diabolic Servitude

When this enchantment enters, return target creature card from your graveyard to the battlefield.
When the creature put onto the battlefield with this enchantment dies, exile it and return this enchantment to its owner's hand.
When this enchantment leaves the battlefield, exile the creature put onto the battlefield with this enchantment.

Rakdos, the Muscle

Flying, trample
Whenever you sacrifice another creature, exile cards equal to its mana value from the top of target player's library. Until your next end step, you may play those cards, and mana of any type can be spent to cast those spells.
Sacrifice another creature: Rakdos gains indestructible until end of turn. Tap it. Activate only once each turn.

Shadowblood Ridge

Liliana's Contract

When this enchantment 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.

Undying Evil

Target creature gains undying until end of turn. (When it dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

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.

Sol Ring

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.

Gray Merchant of Asphodel

When this creature enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Lobber Crew

Defender
{T}: This creature deals 1 damage to each opponent.
Whenever you cast a multicolored spell, untap this creature.

Piranha Marsh

This land enters tapped.
When this land enters, target player loses 1 life.
{T}: Add {B}.

Balefire Dragon

Flying
Whenever this creature deals combat damage to a player, it deals that much damage to each creature that player controls.

Archetype of Aggression

Creatures you control have trample.
Creatures your opponents control lose trample and can't have or gain trample.

Thermo-Alchemist

Defender
{T}: This creature deals 1 damage to each opponent.
Whenever you cast an instant or sorcery spell, untap this creature.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Leechridden Swamp

({T}: Add {B}.)
This land enters tapped.
{B}, {T}: Each opponent loses 1 life. Activate only if you control two or more black permanents.

Archfiend of Despair

Flying
Your opponents can't gain life.
At the beginning of each end step, each opponent loses life equal to the life that player lost this turn. (Damage causes loss of life.)

Blood Speaker

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

Chainer, Dementia Master

All Nightmares get +1/+1.
{B}{B}{B}, Pay 3 life: Put target creature card from a graveyard onto the battlefield under your control. That creature is black and is a Nightmare in addition to its other creature types.
When Chainer leaves the battlefield, exile all Nightmares.

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.

Temple of Malice

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {B} or {R}.

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, then transform it.
Equip {1}

Elbrus, the Binding Blade // Withengar Unbound

Reflecting Pool

{T}: Add one mana of any type that a land you control could produce.

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.

Soul's Fire

Target creature you control deals damage equal to its power to any target.

Barbarian Ring

{T}: Add {R}. This land deals 1 damage to you.
Threshold — {R}, {T}, Sacrifice this land: It deals 2 damage to any target. Activate only if there are seven or more cards in your graveyard.

Knollspine Dragon

Flying
When this creature enters, you may discard your hand and draw cards equal to the damage dealt to target opponent this turn.

Shepherd of Rot

{T}: Each player loses 1 life for each Zombie on the battlefield.

Bloodgift Demon

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

Luxury Suite

This land enters tapped unless you have two or more opponents.
{T}: Add {B} or {R}.

Aurora of Emrakul

Flying, deathtouch
Whenever this creature attacks, each opponent loses 3 life.

Cryptolith Fragment

This artifact enters tapped.
{T}: Add one mana of any color. Each player loses 1 life.
At the beginning of your upkeep, if each player has 10 or less life, transform this artifact.

Cryptolith Fragment // Aurora of Emrakul

Nettle Drone

Devoid (This card has no color.)
{T}: This creature deals 1 damage to each opponent.
Whenever you cast a colorless spell, untap this creature.

Erebos, God of the Dead

Indestructible
As long as your devotion to black is less than five, Erebos isn't a creature. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)
Your opponents can't gain life.
{1}{B}, Pay 2 life: Draw a card.

Spear Spewer

Defender
{T}: This creature deals 1 damage to each player.

Path of Ancestry

This land enters 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.)

Cinderheart Giant

Trample
When this creature dies, it deals 7 damage to a creature an opponent controls chosen at random.

Rakdos, Lord of Riots

You can't cast Rakdos unless an opponent lost life this turn.
Flying, trample
Creature spells you cast cost {1} less to cast for each 1 life your opponents have lost this turn.

Rakdos, Patron of Chaos

Flying, trample
At the beginning of your end step, target opponent may sacrifice two nonland, nontoken permanents of their choice. If they don't, you draw two cards.

Brimstone Trebuchet

Defender, reach
{T}: This creature deals 1 damage to each opponent.
Whenever a Knight you control enters, untap this creature.

Retreat to Hagra

Landfall — Whenever a land you control enters, choose one —
• Target creature gets +1/+0 and gains deathtouch until end of turn.
• Each opponent loses 1 life and you gain 1 life.

Boggart Bog

As this land enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {B}.

Boggart Trawler

When this creature enters, exile target player's graveyard.

Boggart Trawler // Boggart Bog

Tainted Peak

{T}: Add {C}.
{T}: Add {B} or {R}. Activate only if you control a Swamp.

Cunning Sparkmage

Haste
{T}: This creature 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.

Arcane Signet

Etali, Primal Storm

Whenever Etali attacks, exile the top card of each player's library, then you may cast any number of spells from among those cards without paying their mana costs.

Keen Duelist

At the beginning of your upkeep, you and target opponent each reveal the top card of your library. You each lose life equal to the mana value of the card revealed by the other player. You each put the card you revealed into your hand.

Commander's Sphere

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

Trailblazer's Boots

Equipped creature has nonbasic landwalk. (It can't be blocked as long as defending player controls a nonbasic land.)
Equip {2}

Rakdos Carnarium

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {B}{R}.