Pact of Negation

Counter target spell.
At the beginning of your next upkeep, pay {3}{U}{U}. If you don't, you lose the game.

Revelation

Leyline of the Void

If this card is in your opening hand, you may begin the game with it on the battlefield.
If a card would be put into an opponent's graveyard from anywhere, exile it instead.

Forensic Gadgeteer

Whenever you cast an artifact spell, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
Activated abilities of artifacts you control cost {1} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Bloodstained Mire

{T}, Pay 1 life, Sacrifice this land: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Telepathy

Your opponents play with their hands revealed.

Polluted Delta

{T}, Pay 1 life, Sacrifice this land: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Rev, Tithe Extractor

Whenever you attack, target creature gains deathtouch until end of turn.
Whenever one or more creatures you control deal combat damage to a player, create a Treasure token, then look at the top card of that player's library and exile it face down. You may cast that card for as long as it remains exiled. (A Treasure token is an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Swamp

Llanowar Wastes

{T}: Add {C}.
{T}: Add {B} or {G}. This land deals 1 damage to you.

Gonti, Night Minister

Whenever a player casts a spell they don't own, that player creates a Treasure token.
Whenever a creature deals combat damage to one of your opponents, its controller looks at the top card of that opponent's library and exiles it face down. They may play that card for as long as it remains exiled. Mana of any type can be spent to cast a spell this way.

Predators' Hour

Until end of turn, creatures you control gain menace and "Whenever this creature deals combat damage to a player, exile the top card of that player's library face down. You may look at and play that card for as long as it remains exiled, and you may spend mana as though it were mana of any color to cast that spell."

Siphon Insight

Look at the top two cards of target opponent's library. Exile one of them face down and put the other on the bottom of that library. You may play the exiled card for as long as it remains exiled, and you may spend mana as though it were mana of any color to cast that spell.
Flashback {1}{U}{B}

Wizened Snitches

Flying
Players play with the top card of their libraries revealed.

Tezzeret, Master of the Bridge

Creature and planeswalker spells you cast have affinity for artifacts. (They cost {1} less to cast for each artifact you control.)
+2: Tezzeret deals X damage to each opponent, where X is the number of artifacts you control. You gain X life.
−3: Return target artifact card from your graveyard to your hand.
−8: Exile the top ten cards of your library. Put all artifact cards from among them onto the battlefield.

Scalding Tarn

{T}, Pay 1 life, Sacrifice this land: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Windswept Heath

{T}, Pay 1 life, Sacrifice this land: Search your library for a Forest or Plains card, put it onto the battlefield, then shuffle.

Noxious Revival

({G/P} can be paid with either {G} or 2 life.)
Put target card from a graveyard on top of its owner's library.

Cunning Rhetoric

Whenever an opponent attacks you and/or one or more planeswalkers you control, exile the top card of that player's library. You may play that card for as long as it remains exiled, and you may spend mana as though it were mana of any color to cast it.

Talisman of Resilience

{T}: Add {C}.
{T}: Add {B} or {G}. This artifact deals 1 damage to you.

Birds of Paradise

Sol Ring

Strix Serenade

Counter target artifact, creature, or planeswalker spell. Its controller creates a 2/2 blue Bird creature token with flying.

Field of Dreams

Players play with the top card of their libraries revealed.

Reclaim

Put target card from your graveyard on top of your library.

Fierce Guardianship

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

Codex Shredder

{T}: Target player mills a card. (They put the top card of their library into their graveyard.)
{5}, {T}, Sacrifice this artifact: Return target card from your graveyard to your hand.

Pyxis of Pandemonium

{T}: Each player exiles the top card of their library face down.
{7}, {T}, Sacrifice this artifact: Each player turns face up all cards they own exiled with this artifact, then puts all permanent cards among them onto the battlefield.

Deadly Rollick

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

Fellwar Stone

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

Command Tower

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

Gríma, Saruman's Footman

Gríma can't be blocked.
Whenever Gríma deals combat damage to a player, that player exiles cards from the top of their library until they exile an instant or sorcery card. You may cast that card without paying its mana cost. Then that player puts the exiled cards that weren't cast this way on the bottom of their library in a random order.

Xanathar, Guild Kingpin

At the beginning of your upkeep, choose target opponent. Until end of turn, that player can't cast spells, you may look at the top card of their library any time, you may play the top card of their library, and you may spend mana as though it were mana of any color to cast spells this way.

Island

Regrowth

Return target card from your graveyard to your hand.

Tamiyo's Journal

At the beginning of your upkeep, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
{T}, Sacrifice three Clues: Search your library for a card, put that card into your hand, then shuffle.

Curious Inquiry

Enchant creature
Enchanted creature gets +1/+1 and has "Whenever this creature deals combat damage to a player, investigate." (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Misty Rainforest

{T}, Pay 1 life, Sacrifice this land: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

Osgood, Operation Double

{T}: Add {C}. Spend this mana only to cast an artifact spell or activate an ability of an artifact.
Paradox — Whenever you cast a spell from anywhere other than your hand, investigate.
(This token's mana cost is {2}{U}{U}.)

Ancient Tomb

{T}: Add {C}{C}. This land deals 2 damage to you.

Gonti, Canny Acquisitor

Spells you cast but don't own cost {1} less to cast.
Whenever one or more creatures you control deal combat damage to a player, look at the top card of that player's library, then exile it face down. You may play that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Otawara, Soaring City

{T}: Add {U}.
Channel — {3}{U}, Discard this card: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

Delighted Halfling

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a legendary spell, and that spell can't be countered.

Lonis, Cryptozoologist

Whenever another nontoken creature you control enters, investigate.
{T}, Sacrifice X Clues: Target opponent reveals the top X cards of their library. You may put a nonland permanent card with mana value X or less from among them onto the battlefield under your control. That player puts the rest on the bottom of their library in a random order.

Nightveil Specter

Flying
Whenever this creature deals combat damage to a player, that player exiles the top card of their library.
You may play lands and cast spells from among cards exiled with this creature.

Marsh Flats

{T}, Pay 1 life, Sacrifice this land: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

Negate

Treasure

{T}, Sacrifice this token: Add one mana of any color.

Lantern of Insight

Players play with the top card of their libraries revealed.
{T}, Sacrifice this artifact: Target player shuffles.

Clue

Grim Hireling

Whenever one or more creatures you control deal combat damage to a player, create two Treasure tokens.
{B}, Sacrifice X Treasures: Target creature gets -X/-X until end of turn. Activate only as a sorcery.

Dazzling Sphinx

Flying
Whenever this creature deals combat damage to a player, that player exiles cards from the top of their library until they exile an instant or sorcery card. You may cast that card without paying its mana cost. Then that player puts the exiled cards that weren't cast this way on the bottom of their library in a random order.

Fallen Shinobi

Ninjutsu {2}{U}{B} ({2}{U}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever this creature deals combat damage to a player, that player exiles the top two cards of their library. Until end of turn, you may play those cards without paying their mana costs.

Takenuma, Abandoned Mire

{T}: Add {B}.
Channel — {3}{B}, Discard this card: Mill three cards, then return a creature or planeswalker card from your graveyard to your hand. This ability costs {1} less to activate for each legendary creature you control.

Mindbreak Trap

If an opponent cast three or more spells this turn, you may pay {0} rather than pay this spell's mana cost.
Exile any number of target spells.

Overgrown Tomb

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

Wooded Foothills

{T}, Pay 1 life, Sacrifice this land: Search your library for a Mountain or Forest card, put it onto the battlefield, then shuffle.

Force of Negation

If it's not your turn, you may exile a blue card from your hand rather than pay this spell's mana cost.
Counter target noncreature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Exotic Orchard

Force of Will

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost.
Counter target spell.

Talisman of Curiosity

{T}: Add {C}.
{T}: Add {G} or {U}. This artifact deals 1 damage to you.

Thief of Sanity

Flying
Whenever this creature deals combat damage to a player, look at the top three cards of that player's library, exile one of them face down, then put the rest into their graveyard. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Doc Aurlock, Grizzled Genius

Spells you cast from your graveyard or from exile cost {2} less to cast.
Plotting cards from your hand costs {2} less.

False Mourning

Boseiju, Who Endures

{T}: Add {G}.
Channel — {1}{G}, Discard this card: Destroy target artifact, enchantment, or nonbasic land an opponent controls. That player may search their library for a land card with a basic land type, put it onto the battlefield, then shuffle. This ability costs {1} less to activate for each legendary creature you control.

Arcane Signet

Forest

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 this creature: Choose an exiled card an opponent owns with a void counter on it. You may play it this turn without paying its mana cost.

Ongoing Investigation

Whenever one or more creatures you control deal combat damage to a player, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
{1}{G}, Exile a creature card from your graveyard: Investigate. You gain 2 life.

Flooded Strand

{T}, Pay 1 life, Sacrifice this land: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Talisman of Dominance

{T}: Add {C}.
{T}: Add {U} or {B}. This artifact deals 1 damage to you.

Zagoth Triome

({T}: Add {B}, {G}, or {U}.)
This land enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Vampiric Tutor

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

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Watery Grave

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

Mana Leak

Counter target spell unless its controller pays {3}.

Gemstone Caverns

If this card is in your opening hand and you're not the starting player, you may begin the game with Gemstone Caverns on the battlefield with a luck counter on it. If you do, exile a card from your hand.
{T}: Add {C}. If Gemstone Caverns has a luck counter on it, instead add one mana of any color.

Kotis, the Fangkeeper

Indestructible
Whenever Kotis deals combat damage to a player, exile the top X cards of their library, where X is the amount of damage dealt. You may cast any number of spells with mana value X or less from among them without paying their mana costs.

Dream-Thief's Bandana

Whenever equipped creature deals combat damage to a player, look at the top card of their library, then exile it face down. For as long as it remains exiled, you may play it, and mana of any type can be spent to cast that spell.
Equip {1}

Inspiring Statuary

Nonartifact spells you cast have improvise. (Your artifacts can help cast those spells. Each artifact you tap after you're done activating mana abilities pays for {1}.)

Breeding Pool

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

Yavimaya Coast

{T}: Add {C}.
{T}: Add {G} or {U}. This land deals 1 damage to you.

Thada Adel, Acquisitor

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever Thada Adel deals combat damage to a player, search that player's library for an artifact card and exile it. Then that player shuffles. Until end of turn, you may play that card.

Underground River

{T}: Add {C}.
{T}: Add {U} or {B}. This land deals 1 damage to you.

Ghoulcaller's Bell

When you cast this spell, create a token that's a copy of it, except it isn't legendary.
{T}: Add {C}. Spend this mana only to cast an artifact spell or activate an ability of an artifact.
Paradox — Whenever you cast a spell from anywhere other than your hand, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Bird

Memory Lapse

Counter target spell. If that spell is countered this way, put it on top of its owner's library instead of into that player's graveyard.

Imperial Seal

Felix Five-Boots

Menace, ward {2}
If a creature you control dealing combat damage to a player causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Verdant Catacombs

{T}, Pay 1 life, Sacrifice this land: Search your library for a Swamp or Forest card, put it onto the battlefield, then shuffle.