Flare of Denial

You may sacrifice a nontoken blue creature rather than pay this spell's mana cost.
Counter target spell.

Assassin's Trophy

Destroy target permanent an opponent controls. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

Brainstealer Dragon

Flying
At the beginning of your end step, exile the top card of each opponent's library. You may play those cards for as long as they remain exiled. If you cast a spell this way, you may spend mana as though it were mana of any color to cast it.
Whenever a nonland permanent an opponent owns enters the battlefield under your control, they lose life equal to its mana value.

Villainous Wealth

Target opponent exiles the top X cards of their library. You may cast any number of spells with mana value X or less from among them without paying their mana costs.

Savvy Trader

When Savvy Trader enters the battlefield, exile target permanent card from your graveyard. You may play that card for as long as it remains exiled.
Spells you cast from anywhere other than your hand cost {1} less to cast.

Praetor's Grasp

Search target opponent's library for a card and exile it face down. Then that player shuffles. You may look at and play that card for as long as it remains exiled.

Nashi, Moon Sage's Scion

Ninjutsu {3}{B} ({3}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Nashi, Moon Sage's Scion deals combat damage to a player, exile the top card of each player's library. Until end of turn, you may play one of those cards. If you cast a spell this way, pay life equal to its mana value rather than paying its mana cost.

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}

Recurring Insight

Draw cards equal to the number of cards in target opponent's hand.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Ad Nauseam

Reveal the top card of your library and put that card into your hand. You lose life equal to its mana value. You may repeat this process any number of times.

Trygon Predator

Flying
Whenever Trygon Predator deals combat damage to a player, you may destroy target artifact or enchantment that player controls.

Impulse

Look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Strategic Planning

Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.

Blooming Marsh

Blooming Marsh enters the battlefield tapped unless you control two or fewer other lands.
{T}: Add {B} or {G}.

Swamp

Overgrown Tomb

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

Faerie Macabre

Flying
Discard Faerie Macabre: Exile up to two target cards from graveyards.

Notorious Throng

Prowl {5}{U} (You may cast this for its prowl cost if you dealt combat damage to a player this turn with a Rogue.)
Create X 1/1 black Faerie Rogue creature tokens with flying, where X is the damage dealt to your opponents this turn. If this spell's prowl cost was paid, take an extra turn after this one.

Heartless Conscription

Exile all creatures. For each card exiled this way, you may play that card for as long as it remains exiled, and mana of any type can be spent to cast that spell. Exile Heartless Conscription.

Opposition Agent

Flash
You control your opponents while they're searching their libraries.
While an opponent is searching their library, they exile each card they find. You may play those cards for as long as they remain exiled, and you may spend mana as though it were mana of any color to cast them.

Outrageous Robbery

Target opponent exiles the top X cards of their library face down. You may look at and play those cards for as long as they remain exiled. If you cast a spell this way, you may spend mana as though it were mana of any type to cast it.

Sol Ring

Gix, Yawgmoth Praetor

Whenever a creature deals combat damage to one of your opponents, its controller may pay 1 life. If they do, they draw a card.
{4}{B}{B}{B}, Discard X cards: Exile the top X cards of target opponent's library. You may play lands and cast spells from among cards exiled this way without paying their mana costs.

Blade of Selves

Equipped creature has myriad. (Whenever it attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)
Equip {4}

Temple of Deceit

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

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Spiketail Hatchling

Flying (This creature can't be blocked except by creatures with flying or reach.)
Sacrifice Spiketail Hatchling: Counter target spell unless its controller pays {1}.

Mirage Mirror

{2}: Mirage Mirror becomes a copy of target artifact, creature, enchantment, or land until end of turn.

Hedge Maze

({T}: Add {G} or {U}.)
Hedge Maze enters the battlefield tapped.
When Hedge Maze enters the battlefield, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Ruin Raider

Raid — At the beginning of your end step, if you attacked this turn, reveal the top card of your library and put that card into your hand. You lose life equal to the card's mana value.

Looter il-Kor

Shadow (This creature can block or be blocked by only creatures with shadow.)
Whenever Looter il-Kor deals damage to an opponent, draw a card, then discard a card.

Counterspell

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.

Zareth San, the Trickster

Flash
{2}{U}{B}, Return an unblocked attacking Rogue you control to its owner's hand: Put Zareth San, the Trickster from your hand onto the battlefield tapped and attacking.
Whenever Zareth San deals combat damage to a player, you may put target permanent card from that player's graveyard onto the battlefield under your control.

Opulent Palace

Opulent Palace enters the battlefield tapped.
{T}: Add {B}, {G}, or {U}.

Evolving Wilds

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

Necroblossom Snarl

As Necroblossom Snarl enters the battlefield, you may reveal a Swamp or Forest card from your hand. If you don't, Necroblossom Snarl enters the battlefield tapped.
{T}: Add {B} or {G}.

Llanowar Elves

Verdant Catacombs

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

Shipwreck Marsh

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

Compulsive Research

Target player draws three cards. Then that player discards two cards unless they discard a land card.

Thief of Sanity

Flying
Whenever Thief of Sanity 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.

Nightveil Sprite

Flying
Whenever Nightveil Sprite attacks, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Cloud of Faeries

Flying
When Cloud of Faeries enters the battlefield, untap up to two lands.
Cycling {2} ({2}, Discard this card: Draw a card.)

Sylvan Safekeeper

Sacrifice a land: Target creature you control gains shroud until end of turn. (It can't be the target of spells or abilities.)

Abjure

As an additional cost to cast this spell, sacrifice a blue permanent.
Counter target spell.

Snuff Out

If you control a Swamp, you may pay 4 life rather than pay this spell's mana cost.
Destroy target nonblack creature. It can't be regenerated.

Sower of Temptation

Flying
When Sower of Temptation enters the battlefield, gain control of target creature for as long as Sower of Temptation remains on the battlefield.

Lonis, Cryptozoologist

Whenever another nontoken creature enters the battlefield under your control, 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.

Craterhoof Behemoth

Haste
When Craterhoof Behemoth enters the battlefield, creatures you control gain trample and get +X/+X until end of turn, where X is the number of creatures you control.

Mercurial Spelldancer

Mercurial Spelldancer can't be blocked.
Whenever you cast a noncreature spell, put an oil counter on Mercurial Spelldancer.
Whenever Mercurial Spelldancer deals combat damage to a player, you may remove two oil counters from it. If you do, when you next cast an instant or sorcery spell this turn, copy that spell. You may choose new targets for the copy.

Druids' Repository

Whenever a creature you control attacks, put a charge counter on Druids' Repository.
Remove a charge counter from Druids' Repository: Add one mana of any color.

Arcane Signet

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

Hostage Taker

When Hostage Taker enters the battlefield, exile another target creature or artifact until Hostage Taker leaves the battlefield. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Whirler Rogue

When Whirler Rogue enters the battlefield, create two 1/1 colorless Thopter artifact creature tokens with flying.
Tap two untapped artifacts you control: Target creature can't be blocked this turn.

Etrata, the Silencer

Etrata, the Silencer can't be blocked.
Whenever Etrata deals combat damage to a player, exile target creature that player controls and put a hit counter on that card. That player loses the game if they own three or more exiled cards with hit counters on them. Etrata's owner shuffles Etrata into their library.

Thada Adel, Acquisitor

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever Thada Adel, Acquisitor 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.

Terramorphic Expanse

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

Island

Hinterland Harbor

Hinterland Harbor enters the battlefield tapped unless you control a Forest or an Island.
{T}: Add {G} or {U}.

Overflowing Basin

Lightning Greaves

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

Sunken Ruins

{T}: Add {C}.
{U/B}, {T}: Add {U}{U}, {U}{B}, or {B}{B}.

Thieving Skydiver

Kicker {X}. X can't be 0. (You may pay an additional {X} as you cast this spell.)
Flying
When Thieving Skydiver enters the battlefield, if it was kicked, gain control of target artifact with mana value X or less. If that artifact is an Equipment, attach it to Thieving Skydiver.

Baleful Strix

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

Skullclamp

Equipped creature gets +1/-1.
Whenever equipped creature dies, draw two cards.
Equip {1}

Sakashima's Student

Ninjutsu {1}{U} ({1}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
You may have Sakashima's Student enter the battlefield as a copy of any creature on the battlefield, except it's a Ninja in addition to its other creature types.

Gonti, Lord of Luxury

Deathtouch
When Gonti, Lord of Luxury enters the battlefield, look at the top four cards of target opponent's library, exile one of them face down, then put the rest on the bottom of that library in a random order. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Petty Theft

Return target nonland permanent an opponent controls to its owner's hand.

Brazen Borrower

Flash
Flying
Brazen Borrower can block only creatures with flying.

Brazen Borrower // Petty Theft

Thieving Varmint

Deathtouch, lifelink
{T}, Pay 1 life: Add two mana of any one color. Spend this mana only to cast spells you don't own.

Wharf Infiltrator

Skulk (This creature can't be blocked by creatures with greater power.)
Whenever Wharf Infiltrator deals combat damage to a player, you may draw a card. If you do, discard a card.
Whenever you discard a creature card, you may pay {2}. If you do, create a 3/2 colorless Eldrazi Horror creature token.

Forest

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."

Edric, Spymaster of Trest

Whenever a creature deals combat damage to one of your opponents, its controller may draw a card.

Darkslick Shores

Darkslick Shores enters the battlefield tapped unless you control two or fewer other lands.
{T}: Add {U} or {B}.

Choked Estuary

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

Cephalid Facetaker

Cephalid Facetaker can't be blocked.
At the beginning of combat on your turn, you may have Cephalid Facetaker become a copy of another target creature until end of turn, except it's 1/4 and has "This creature can't be blocked."

Botanical Sanctum

Botanical Sanctum enters the battlefield tapped unless you control two or fewer other lands.
{T}: Add {G} or {U}.

Vineglimmer Snarl

As Vineglimmer Snarl enters the battlefield, you may reveal a Forest or Island card from your hand. If you don't, Vineglimmer Snarl enters the battlefield tapped.
{T}: Add {G} or {U}.

Siren Stormtamer

Flying
{U}, Sacrifice Siren Stormtamer: Counter target spell or ability that targets you or a creature you control.

Polluted Delta

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

Beastmaster Ascension

Whenever a creature you control attacks, you may put a quest counter on Beastmaster Ascension.
As long as Beastmaster Ascension has seven or more quest counters on it, creatures you control get +5/+5.

Viridescent Bog

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.

Knowledge Exploitation

Prowl {3}{U} (You may cast this for its prowl cost if you dealt combat damage to a player this turn with a Rogue.)
Search target opponent's library for an instant or sorcery card. You may cast that card without paying its mana cost. Then that player shuffles.

Coiling Oracle

When Coiling Oracle enters the battlefield, reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put that card into your hand.