Sengir, the Dark Baron

Flying
Whenever another creature dies, put two +1/+1 counters on Sengir, the Dark Baron.
Whenever another player loses the game, you gain life equal to that player's life total as the turn began.
Partner (You can have two commanders if both have partner.)

Evolving Wilds

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

Jet Medallion

Black spells you cast cost {1} less to cast.

Desecration Elemental

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
Whenever a player casts a spell, sacrifice a creature.

Blighted Agent

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Blighted Agent can't be blocked.

Invisible Stalker

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Invisible Stalker can't be blocked.

Steel Golem

Bloodthirsty Blade

Equipped creature gets +2/+0 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
{1}: Attach Bloodthirsty Blade to target creature an opponent controls. Activate only as a sorcery.

Accursed Marauder

When Accursed Marauder enters, each player sacrifices a nontoken creature of their choice.

Notion Thief

Flash
If an opponent would draw a card except the first one they draw in each of their draw steps, instead that player skips that draw and you draw a card.

Vraska's Fall

Each opponent sacrifices a creature or planeswalker of their choice and gets a poison counter.

Thought Reflection

If you would draw a card, draw two cards instead.

Dark Ritual

Twenty-Toed Toad

Your maximum hand size is twenty.
Whenever you attack with two or more creatures, put a +1/+1 counter on Twenty-Toed Toad and draw a card.
Whenever Twenty-Toed Toad attacks, you win the game if there are twenty or more counters on it or you have twenty or more cards in hand.

Arcane Signet

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

Morbid Opportunist

Whenever one or more other creatures die, draw a card. This ability triggers only once each turn.

Sanguine Bond

Whenever you gain life, target opponent loses that much life.

Greater Harvester

At the beginning of your upkeep, sacrifice a permanent.
Whenever Greater Harvester deals combat damage to a player, that player sacrifices two permanents of their choice.

Tormented Soul

Tormented Soul can't block and can't be blocked.

Counterspell

Diabolic Tutor

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

Thought Devourer

Flying
Your maximum hand size is reduced by four.

Phyrexian Vatmother

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
At the beginning of your upkeep, you get a poison counter.

No Mercy

Whenever a creature deals damage to you, destroy 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, Unshackled.

Jon Irenicus, Shattered One

At the beginning of your end step, target opponent gains control of up to one target creature you control. Put two +1/+1 counters on it and tap it. It's goaded for the rest of the game and it gains "This creature can't be sacrificed." (It attacks each combat if able and attacks a player other than you if able.)
Whenever a creature you own but don't control attacks, you draw a card.

Priest of the Blood Rite

When Priest of the Blood Rite enters, create a 5/5 black Demon creature token with flying.
At the beginning of your upkeep, you lose 2 life.

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.

Phyrexian Negator

Trample
Whenever Phyrexian Negator is dealt damage, sacrifice that many permanents.

Baleful Strix

Flying, deathtouch
When Baleful Strix enters, draw a card.

Shadowborn Demon

Flying
When Shadowborn Demon enters, 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.

Rust Elemental

Flying
At the beginning of your upkeep, sacrifice an artifact other than Rust Elemental. If you can't, tap Rust Elemental and you lose 4 life.

Sygg, River Cutthroat

At the beginning of each end step, if an opponent lost 3 or more life this turn, you may draw a card. (Damage causes loss of life.)

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Ghoulish Procession

Whenever one or more nontoken creatures die, create a 2/2 black Zombie creature token with decayed. This ability triggers only once each turn. (A creature with decayed can't block. When it attacks, sacrifice it at end of combat.)

Gutwrencher Oni

Trample
At the beginning of your upkeep, discard a card if you don't control an Ogre.

Liege of the Pit

Flying, trample
At the beginning of your upkeep, sacrifice a creature other than Liege of the Pit. If you can't, Liege of the Pit deals 7 damage to you.
Morph {B}{B}{B}{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.)

Swamp

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Pestilent Syphoner

Flying
Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)

Hellcarver Demon

Flying
Whenever Hellcarver Demon deals combat damage to a player, sacrifice all other permanents you control and discard your hand. Exile the top six cards of your library. You may cast any number of spells from among cards exiled this way without paying their mana costs.

Triton Shorestalker

Vampire Lacerator

At the beginning of your upkeep, you lose 1 life unless an opponent has 10 or less life.

Clone

You may have Clone enter as a copy of any creature on the battlefield.

Ebonblade Reaper

Whenever Ebonblade Reaper attacks, you lose half your life, rounded up.
Whenever Ebonblade Reaper deals combat damage to a player, that player loses half their life, rounded up.
Morph {3}{B}{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.)

Flesh Reaver

Whenever Flesh Reaver deals damage to a creature or opponent, Flesh Reaver deals that much damage to you.

Phyrexian Soulgorger

Cumulative upkeep—Sacrifice a creature. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)

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.

Plaguecrafter

When Plaguecrafter enters, each player sacrifices a creature or planeswalker of their choice. Each player who can't discards a card.

Agent of the Iron Throne

Commander creatures you own have "Whenever an artifact or creature you control is put into a graveyard from the battlefield, each opponent loses 1 life."

Skithiryx, the Blight Dragon

Flying
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{B}: Skithiryx, the Blight Dragon gains haste until end of turn.
{B}{B}: Regenerate Skithiryx.

Wretched Anurid

Whenever another creature enters, you lose 1 life.

Irenicus's Vile Duplication

Create a token that's a copy of target creature you control, except the token has flying and it isn't legendary.

Master of the Feast

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

Grid Monitor

Black Market

Whenever a creature dies, put a charge counter on Black Market.
At the beginning of your first main phase, add {B} for each charge counter on Black Market.

Phyrexian Juggernaut

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Phyrexian Juggernaut attacks each combat if able.

Resculpt

Exile target artifact or creature. Its controller creates a 4/4 blue and red Elemental creature token.

Teferi's Ageless Insight

If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

Core Prowler

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
When Core Prowler dies, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Sleeper Agent

When Sleeper Agent enters, target opponent gains control of it.
At the beginning of your upkeep, Sleeper Agent deals 2 damage to you.

Myriad Landscape

Myriad Landscape enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Dauthi Voidwalker

Shadow (This creature can block or be blocked by only creatures with shadow.)
If a card would be put into an opponent's graveyard from anywhere, instead exile it with a void counter on it.
{T}, Sacrifice Dauthi Voidwalker: Choose an exiled card an opponent owns with a void counter on it. You may play it this turn without paying its mana cost.

Island

Rotting Regisaur

At the beginning of your upkeep, discard a card.

Deadly Rollick

If you control a commander, you may cast this spell without paying its mana cost.
Exile target creature.

Blackblade Reforged

Equipped creature gets +1/+1 for each land you control.
Equip legendary creature {3}
Equip {7}

Plague Stinger

Flying
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Negate

Prologue to Phyresis

Each opponent gets a poison counter.
Draw a card.

Morkrut Necropod

Menace (This creature can't be blocked except by two or more creatures.)
Whenever Morkrut Necropod attacks or blocks, sacrifice another creature or land.

Abhorrent Overlord

Flying
When Abhorrent Overlord enters, create a number of 1/1 black Harpy creature tokens with flying equal to your devotion to black. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)
At the beginning of your upkeep, sacrifice a creature.

Thought Eater

Flying
Your maximum hand size is reduced by three.

Command Tower

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Lord of the Pit

Flying, trample
At the beginning of your upkeep, sacrifice a creature other than Lord of the Pit. If you can't, Lord of the Pit deals 7 damage to you.

Thought Vessel

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

Vampiric Tutor

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Wizard Class

(Gain the next level as a sorcery to add its ability.)
You have no maximum hand size.
{2}{U}: Level 2
When this Class becomes level 2, draw two cards.
{4}{U}: Level 3
Whenever you draw a card, put a +1/+1 counter on target creature you control.

Thought Nibbler

Flying
Your maximum hand size is reduced by two.

Coveted Falcon

Flying
Whenever Coveted Falcon attacks, gain control of target permanent you own but don't control.
Disguise {1}{U}
When Coveted Falcon is turned face up, target opponent gains control of any number of target permanents you control. Draw a card for each one they gained control of this way.

Rise of the Dread Marn

Create X 2/2 black Zombie Berserker creature tokens, where X is the number of nontoken creatures that died this turn.
Foretell {B} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Dimir Signet

Exquisite Blood

Whenever an opponent loses life, you gain that much life.

Sol Ring

Falkenrath Noble

Flying
Whenever Falkenrath Noble or another creature dies, target player loses 1 life and you gain 1 life.

Demonic Taskmaster

Flying
At the beginning of your upkeep, sacrifice a creature other than Demonic Taskmaster.

Ogre Slumlord

Whenever another nontoken creature dies, you may create a 1/1 black Rat creature token.
Rats you control have deathtouch.

Night's Whisper

Grinning Demon

At the beginning of your upkeep, you lose 2 life.
Morph {2}{B}{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.)

Relentless Rats

Relentless Rats gets +1/+1 for each other creature on the battlefield named Relentless Rats.
A deck can have any number of cards named Relentless Rats.

Rite of Belzenlok

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Create two 0/1 black Cleric creature tokens.
III — Create a 6/6 black Demon creature token with flying, trample, and "At the beginning of your upkeep, sacrifice another creature. If you can't, this creature deals 6 damage to you."

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

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.)

Abyssal Persecutor

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

Ebon Drake

Flying
Whenever a player casts a spell, you lose 1 life.

Plague Reaver

At the beginning of your end step, sacrifice each other creature you control.
Discard two cards, Sacrifice Plague Reaver: Choose target opponent. Return Plague Reaver to the battlefield under that player's control at the beginning of their next upkeep.

Mithril Coat

Flash
Indestructible
When Mithril Coat enters, attach it to target legendary creature you control.
Equipped creature has indestructible.
Equip {3}

Vashta Nerada

Indestructible
Shadow (This creature can block or be blocked by only creatures with shadow.)
Morbid — At the beginning of each end step, if a creature died this turn, put a +1/+1 counter on Vashta Nerada.

Reaper from the Abyss

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

Biotransference

Creatures you control are artifacts in addition to their other types. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.
Whenever you cast an artifact spell, you lose 1 life and create a 2/2 black Necron Warrior artifact creature token.

Malleable Impostor

Flash
Flying
You may have Malleable Impostor enter as a copy of a creature an opponent controls, except it's a Faerie Shapeshifter in addition to its other types and it has flying.

Damnation

Destroy all creatures. They can't be regenerated.

Drinker of Sorrow

Drinker of Sorrow can't block.
Whenever Drinker of Sorrow deals combat damage, sacrifice a permanent.

Blood Artist

Whenever Blood Artist or another creature dies, target player loses 1 life and you gain 1 life.

Sheoldred's Headcleaver

Menace
Toxic 2 (Players dealt combat damage by this creature also get two poison counters.)