Dark Suspicions

At the beginning of each opponent's upkeep, that player loses X life, where X is the number of cards in that player's hand minus the number of cards in your hand.

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.

Smoldering Marsh

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

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.

Reanimate

Put target creature card from a graveyard onto the battlefield under your control. You lose life equal to its mana value.

Sign in Blood

Target player draws two cards and loses 2 life.

Kokusho, the Evening Star

Flying
When Kokusho dies, each opponent loses 5 life. You gain life equal to the life lost this way.

Terminate

Destroy target creature. It can't be regenerated.

Exsanguinate

Each opponent loses X life. You gain life equal to the life lost this way.

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.

Vial Smasher the Fierce

Whenever you cast your first spell each turn, choose an opponent at random. Vial Smasher deals damage equal to that spell's mana value to that player or a planeswalker that player controls.
Partner (You can have two commanders if both have partner.)

Angrath, the Flame-Chained

+1: Each opponent discards a card and loses 2 life.
−3: Gain control of target creature until end of turn. Untap it. It gains haste until end of turn. Sacrifice it at the beginning of the next end step if it has mana value 3 or less.
−8: Each opponent loses life equal to the number of cards in their graveyard.

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.

Court of Ire

When this enchantment enters, you become the monarch.
At the beginning of your upkeep, this enchantment deals 2 damage to any target. If you're the monarch, it deals 7 damage instead.

Quakebringer

Your opponents can't gain life.
At the beginning of your upkeep, Quakebringer deals 2 damage to each opponent. This ability triggers only if Quakebringer is on the battlefield or if Quakebringer is in your graveyard and you control a Giant.
Foretell {2}{R}{R}

Bloodgift Demon

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

Mudslide

Creatures without flying don't untap during their controllers' untap steps.
At the beginning of each player's upkeep, that player may choose any number of tapped creatures without flying they control and pay {2} for each creature chosen this way. If the player does, untap those creatures.

Read the Bones

Scry 2, then draw two cards. You lose 2 life. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Rune-Scarred Demon

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

Extinguish All Hope

Revenge of Ravens

Whenever a creature attacks you or a planeswalker you control, that creature's controller loses 1 life and you gain 1 life.

Stensia Bloodhall

{T}: Add {C}.
{3}{B}{R}, {T}: This land deals 2 damage to target player or planeswalker.

Triskaidekaphobia

At the beginning of your upkeep, choose one —
• Each player with exactly 13 life loses the game, then each player gains 1 life.
• Each player with exactly 13 life loses the game, then each player loses 1 life.

Luxury Suite

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

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Kaervek the Merciless

Whenever an opponent casts a spell, Kaervek deals damage equal to that spell's mana value to any target.

Forgotten Cave

This land enters tapped.
{T}: Add {R}.
Cycling {R} ({R}, Discard this card: Draw a card.)

Damnation

Destroy all creatures. They can't be regenerated.

Sin Prodder

Menace
At the beginning of your upkeep, reveal the top card of your library. Any opponent may have you put that card into your graveyard. If a player does, this creature deals damage to that player equal to that card's mana value. Otherwise, put that card into your hand.

Dragonskull Summit

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

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.

Swamp

War's Toll

Whenever an opponent taps a land for mana, tap all lands that player controls.
If a creature an opponent controls attacks, all creatures that opponent controls attack if able.

Hero's Downfall

Master of Cruelties

First strike, deathtouch
This creature can only attack alone.
Whenever this creature attacks a player and isn't blocked, that player's life total becomes 1. This creature assigns no combat damage this combat.

Victim of Night

Destroy target non-Vampire, non-Werewolf, non-Zombie creature.

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.

Endless Atlas

{2}, {T}: Draw a card. Activate only if you control three or more lands with the same name.

Coalition Relic

{T}: Add one mana of any color.
{T}: Put a charge counter on this artifact.
At the beginning of your first main phase, remove all charge counters from this artifact. Add one mana of any color for each charge counter removed this way.

Blood Crypt

({T}: Add {B} or {R}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Fiendish Duo

First strike (This creature deals combat damage before creatures without first strike.)
If a source would deal damage to an opponent, it deals double that damage to that player instead.

Dreadbore

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.)

Eyeblight's Ending

Animate Dead

Enchant creature card in a graveyard
When this Aura enters, if it's on the battlefield, it loses "enchant creature card in a graveyard" and gains "enchant creature put onto the battlefield with this Aura." Return enchanted creature card to the battlefield under your control and attach this Aura to it. When this Aura leaves the battlefield, that creature's controller sacrifices it.
Enchanted creature gets -1/-0.

Court of Ambition

When this enchantment enters, you become the monarch.
At the beginning of your upkeep, each opponent loses 3 life unless they discard a card. If you're the monarch, instead each opponent loses 6 life unless they discard two cards.

Wheel of Fate

Suspend 4—{1}{R} (Rather than cast this card from your hand, pay {1}{R} and exile it with four time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
Each player discards their hand, then draws seven cards.

Combustible Gearhulk

First strike
When this creature enters, target opponent may have you draw three cards. If the player doesn't, you mill three cards, then this creature deals damage to that player equal to the total mana value of those cards.

Torment of Hailfire

Repeat the following process X times. Each opponent loses 3 life unless that player sacrifices a nonland permanent of their choice or discards a card.

Abyssal Persecutor

Flying, trample
You can't win the game and your opponents can't lose the game.

Blood Sun

When this enchantment enters, draw a card.
All lands lose all abilities except mana abilities.

Dismember

({B/P} can be paid with either {B} or 2 life.)
Target creature gets -5/-5 until end of turn.

Akoum Refuge

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {B} or {R}.

Go for the Throat

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.

Crux of Fate

Choose one —
• Destroy all Dragon creatures.
• Destroy all non-Dragon creatures.

Price of Progress

Price of Progress deals damage to each player equal to twice the number of nonbasic lands that player controls.

Blood Moon

Arcane Signet

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

Painful Quandary

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

No Mercy

Whenever a creature deals damage to you, destroy it.

Rakdos's Return

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

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.

Mountain

Dire Fleet Ravager

Menace, deathtouch
When this creature enters, each player loses a third of their life, rounded up.

Ob Nixilis Reignited

+1: You draw a card and you lose 1 life.
−3: Destroy target creature.
−8: Target opponent gets an emblem with "Whenever a player draws a card, you lose 2 life."

Palace Siege

As this enchantment enters, choose Khans or Dragons.
• Khans — At the beginning of your upkeep, return target creature card from your graveyard to your hand.
• Dragons — At the beginning of your upkeep, each opponent loses 2 life and you gain 2 life.

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.

Rampaging Ferocidon

Menace
Players can't gain life.
Whenever another creature enters, this creature deals 1 damage to that creature's controller.

Lightning Greaves

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

Shadowblood Ridge

Smoke

Players can't untap more than one creature during their untap steps.

Languish

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

Great Unclean One

Reverberating Summons — At the beginning of your end step, each opponent loses 2 life. Then for each opponent who has less life than you, create a 1/3 black Demon creature token named Plaguebearer of Nurgle.

Mogis, God of Slaughter

Indestructible
As long as your devotion to black and red is less than seven, Mogis isn't a creature.
At the beginning of each opponent's upkeep, Mogis deals 2 damage to that player unless they sacrifice a creature of their choice.