Thought Devourer

Flying
Your maximum hand size is reduced by four.

Reject Imperfection

Counter target spell. If that spell's mana value was 3 or less, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Counterspell

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.

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.)

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.)

Yukora, the Prisoner

When Yukora, the Prisoner leaves the battlefield, sacrifice all non-Ogre creatures you control.

Temple of Deceit

Temple of Deceit enters tapped.
When Temple of Deceit enters, scry 1.
{T}: Add {U} or {B}.

Switcheroo

Exchange control of two target creatures.

Steel Golem

Vraska's Fall

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

Demonic Taskmaster

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

Flesh Reaver

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

Dissipation Field

Whenever a permanent deals damage to you, return it to its owner's hand.

Neurok Stealthsuit

Equipped creature has shroud. (It can't be the target of spells or abilities.)
{U}{U}: Attach Neurok Stealthsuit to target creature you control.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Evil Eye of Urborg

Non-Eye creatures you control can't attack.
Whenever Evil Eye of Urborg becomes blocked by a creature, destroy that creature.

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.

Phyresis

Enchant creature
Enchanted creature has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Tainted Isle

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

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Commander's Sphere

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

Thought Eater

Flying
Your maximum hand size is reduced by three.

Tainted Strike

Target creature gets +1/+0 and gains infect until end of turn. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Prologue to Phyresis

Each opponent gets a poison counter.
Draw a card.

Filter Out

Return all noncreature, nonland permanents to their owners' hands.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

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.)

Psychic Impetus

Enchant creature
Enchanted creature gets +2/+2 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, you scry 2.

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.

Archfiend of the Dross

Flying
Archfiend of the Dross enters with four oil counters on it.
At the beginning of your upkeep, remove an oil counter from Archfiend of the Dross. Then if it has no oil counters on it, you lose the game.
Whenever a creature an opponent controls dies, its controller loses 2 life.

Aetherize

Return all attacking creatures to their owner's hand.

Thought Vessel

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

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.)

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.

Shipwreck Marsh

Shipwreck Marsh enters tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

Modify Memory

Exchange control of two target creatures controlled by different players. If you control neither creature, draw three cards.

Serum Snare

Return target nonland permanent to its owner's hand. If that permanent had mana value 3 or less, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Evil Eye of Orms-by-Gore

Non-Eye creatures you control can't attack.
Evil Eye of Orms-by-Gore can't be blocked except by Walls.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Parasitic Impetus

Enchant creature
Enchanted creature gets +2/+2 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, its controller loses 2 life and you gain 2 life.

Wrong Turn

Target opponent gains control of target creature. (If an attacking or blocking creature changes controllers, it's removed from combat.)

Ichor Rats

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
When Ichor Rats enters, each player gets a poison counter.

Drinker of Sorrow

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

Heartless Summoning

Creature spells you cast cost {2} less to cast.
Creatures you control get -1/-1.

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.

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.

Negate

Choked Estuary

As Choked Estuary enters, you may reveal an Island or Swamp card from your hand. If you don't, Choked Estuary enters tapped.
{T}: Add {U} or {B}.

Ringsight

The Ring tempts you. Search your library for a card that shares a color with a legendary creature you control, reveal it, put it into your hand, then shuffle.

Island

Infectious Inquiry

You draw two cards and you lose 2 life. Each opponent gets a poison counter.

Mind Stone

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

Darkwater Catacombs

Ebon Drake

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

Experimental Augury

Look at the top three cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

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.

Command Tower

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

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.

Countersquall

Counter target noncreature spell. Its controller loses 2 life.

Swiftfoot Boots

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

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.

Wretched Anurid

Whenever another creature enters, you lose 1 life.

Phyrexian Negator

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

Rotting Regisaur

At the beginning of your upkeep, discard 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.

Dimir Signet

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.

Mocking Doppelganger

Flash
You may have Mocking Doppelganger enter as a copy of a creature an opponent controls, except it has "Other creatures with the same name as this creature are goaded." (They attack each combat if able and attack a player other than you if able.)

Drowned Catacomb

Drowned Catacomb enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Fateful Handoff

Draw cards equal to the mana value of target artifact or creature you control. An opponent gains control of that permanent.

Swamp

Run Away Together

Choose two target creatures controlled by different players. Return those creatures to their owners' hands.

Arcane Signet

Sunken Hollow

({T}: Add {U} or {B}.)
Sunken Hollow enters tapped unless you control two or more basic lands.

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.)

Sol Ring

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.