Ashiok, Nightmare Muse

+1: Create a 2/3 blue and black Nightmare creature token with "Whenever this creature attacks or blocks, each opponent exiles the top two cards of their library."
−3: Return target nonland permanent to its owner's hand, then that player exiles a card from their hand.
−7: You may cast up to three spells from among face-up cards your opponents own from exile without paying their mana costs.

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Rotting Giant

Whenever Rotting Giant attacks or blocks, sacrifice it unless you exile a card from your graveyard.

Ill-Gotten Inheritance

At the beginning of your upkeep, Ill-Gotten Inheritance deals 1 damage to each opponent and you gain 1 life.
{5}{B}, Sacrifice Ill-Gotten Inheritance: It deals 4 damage to target opponent and you gain 4 life.

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.

Painful Quandary

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

Andradite Leech

Black spells you cast cost {B} more to cast.
{B}: Andradite Leech gets +1/+1 until end of turn.

Sapphire Leech

Flying
Blue spells you cast cost {U} more to cast.

Sheoldred's Edict

Choose one —
• Each opponent sacrifices a nontoken creature of their choice.
• Each opponent sacrifices a creature token of their choice.
• Each opponent sacrifices a planeswalker of their choice.

Blue Sun's Twilight

Gain control of target creature with mana value X or less. If X is 5 or more, create a token that's a copy of that creature.

Diabolic Tutor

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

Darkwater Catacombs

Phyrexian Infiltrator

{2}{U}{U}: Exchange control of Phyrexian Infiltrator and target creature. (This effect lasts indefinitely.)

Identity Thief

Whenever Identity Thief attacks, you may exile another target nontoken creature. If you do, Identity Thief becomes a copy of that creature until end of turn. Return the exiled card to the battlefield under its owner's control at the beginning of the next end step.

Soulless Jailer

Permanent cards in graveyards can't enter the battlefield.
Players can't cast noncreature spells from graveyards or exile.

Command Tower

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

Rotting Regisaur

At the beginning of your upkeep, discard a card.

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}.

Phantasmal Dreadmaw

Trample
When Phantasmal Dreadmaw becomes the target of a spell or ability, sacrifice it.

In Garruk's Wake

Destroy all creatures you don't control and all planeswalkers you don't control.

Reflecting Pool

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

Underworld Charger

Underworld Charger can't block.
Escape—{4}{B}, Exile three other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)
Underworld Charger escapes with two +1/+1 counters on it.

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.)

Lightning Greaves

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

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.

Persuasion

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
You control enchanted creature.

Island

Expendable Lackey

{1}{U}, Exile Expendable Lackey from your graveyard: Create a 1/1 blue Fish creature token with "This creature can't be blocked." Activate only as a sorcery.

Thought Devourer

Flying
Your maximum hand size is reduced by four.

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Mass Manipulation

Gain control of X target creatures and/or planeswalkers.

Invoke the Winds

Gain control of target artifact or creature. Untap it.

Negate

Thought Eater

Flying
Your maximum hand size is reduced by three.

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.

Inevitable End

Enchant creature
Enchanted creature has "At the beginning of your upkeep, sacrifice a creature."

In Too Deep

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Enchant creature, planeswalker, or Clue
Enchanted permanent is a colorless Clue artifact with "{2}, Sacrifice this artifact: Draw a card" and loses all other abilities. (It's no longer a creature or planeswalker.)

Graf Reaver

Exploit (When this creature enters, you may sacrifice a creature.)
When Graf Reaver exploits a creature, destroy target planeswalker.
At the beginning of your upkeep, Graf Reaver deals 1 damage to you.

Flood of Tears

Return all nonland permanents to their owners' hands. If you return four or more nontoken permanents you control this way, you may put a permanent card from your hand onto the battlefield.

In Bolas's Clutches

Enchant permanent
You control enchanted permanent.
Enchanted permanent is legendary.

Burnished Hart

{3}, Sacrifice this creature: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Web of Inertia

At the beginning of combat on each opponent's turn, that player may exile a card from their graveyard. If the player doesn't, creatures they control can't attack you this turn.

Underworld Dreams

Whenever an opponent draws a card, Underworld Dreams deals 1 damage to that player.

Ravenous Chupacabra

When Ravenous Chupacabra enters, destroy target creature an opponent controls.

Sunken Hollow

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

Pilfering Imp

Flying
{1}{B}, {T}, Sacrifice Pilfering Imp: Target opponent reveals their hand. You choose a nonland card from it. That player discards that card. Activate only as a sorcery.

Thought Vessel

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

Arcane Signet

Creeping Tar Pit

Creeping Tar Pit enters tapped.
{T}: Add {U} or {B}.
{1}{U}{B}: Creeping Tar Pit becomes a 3/2 blue and black Elemental creature until end of turn and can't be blocked this turn. It's still a land.

River of Tears

{T}: Add {U}. If you played a land this turn, add {B} instead.

Shimmering Wings

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
Enchanted creature has flying. (It can't be blocked except by creatures with flying or reach.)
{U}: Return Shimmering Wings to its owner's hand.

Sol Ring

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.

Withercrown

Enchant creature
Enchanted creature has base power 0 and has "At the beginning of your upkeep, you lose 1 life unless you sacrifice this creature."

Sleeper's Robe

Enchant creature
Enchanted creature has fear. (It can't be blocked except by artifact creatures and/or black creatures.)
Whenever enchanted creature deals combat damage to an opponent, you may draw a card.

Stirge

Flying
Stirge can't block.
Blood Drain — {1}{B}, Pay 1 life, Sacrifice Stirge: Draw a card.

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Plague Spitter

At the beginning of your upkeep, Plague Spitter deals 1 damage to each creature and each player.
When Plague Spitter dies, it deals 1 damage to each creature and each player.

Stalking Assassin

{3}{U}, {T}: Tap target creature.
{3}{B}, {T}: Destroy target tapped creature.

Nadir Kraken

Whenever you draw a card, you may pay {1}. If you do, put a +1/+1 counter on Nadir Kraken and create a 1/1 blue Tentacle creature token.

Persistent Specimen

{2}{B}: Return Persistent Specimen from your graveyard to the battlefield tapped.

Chamber of Manipulation

Enchant land
Enchanted land has "{T}, Discard a card: Gain control of target creature until end of turn."

Swamp

Razorlash Transmogrant

Razorlash Transmogrant can't block.
{4}{B}{B}: Return Razorlash Transmogrant from your graveyard to the battlefield with a +1/+1 counter on it. This ability costs {4} less to activate if an opponent controls four or more nonbasic lands.

Thought Nibbler

Flying
Your maximum hand size is reduced by two.

Dimir Signet

Watery Grave

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

Hurkyl's Final Meditation

During turns other than yours, this spell costs {3} more to cast.
Return all nonland permanents to their owners' hands. End the turn. (Exile all spells and abilities from the stack, including this card. The player whose turn it is discards down to their maximum hand size. Damage wears off, and "this turn" and "until end of turn" effects end.)

Baleful Strix

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

Vile Consumption

All creatures have "At the beginning of your upkeep, sacrifice this creature unless you pay 1 life."

Temple of Deceit

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 {U} or {B}.

Feed the Swarm

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