Enchant creature
Enchanted creature has flying and "Whenever this creature deals combat damage to a player, venture into the dungeon." (Enter the first room or advance to the next room.)

Make Disappear

Casualty 1 (As you cast this spell, you may sacrifice a creature with power 1 or greater. When you do, copy this spell and you may choose a new target for the copy.)
Counter target spell unless its controller pays {2}.

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.

Clever Conjurer

Mage Hand — {T}: Untap target permanent not named Clever Conjurer. Activate only as a sorcery.

A Little Chat

Casualty 1 (As you cast this spell, you may sacrifice a creature with power 1 or greater. When you do, copy this spell.)
Look at the top two cards of your library. Put one of them into your hand and the other on the bottom of your library.

Gelatinous Cube

Engulf — When Gelatinous Cube enters the battlefield, exile target non-Ooze creature an opponent controls until Gelatinous Cube leaves the battlefield.
Dissolve — {X}{B}: Put target creature card with mana value X exiled with Gelatinous Cube into its owner's graveyard.

Command Tower

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

An Offer You Can't Refuse

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

Death-Priest of Myrkul

Skeletons, Vampires, and Zombies you control get +1/+1.
At the beginning of your end step, if a creature died this turn, you may pay {1}. If you do, create a 1/1 black Skeleton creature token.

Put Away

Counter target spell. You may shuffle up to one target card from your graveyard into your library.

Bone to Ash

Counter target creature spell.
Draw a card.

Tortured Existence

{B}, Discard a creature card: Return target creature card from your graveyard to your hand.

Bar the Gate

Counter target creature or planeswalker spell. Venture into the dungeon. (Enter the first room or advance to the next room.)

Power of Persuasion

Choose target creature an opponent controls, then roll a d20.
1—9 | Return it to its owner's hand.
10—19 | Its owner puts it on the top or bottom of their library.
20 | Gain control of it until the end of your next turn.

Deal Gone Bad

Target creature gets -3/-3 until end of turn. Target player mills three cards. (They put the top three cards of their library into their graveyard.)

Mordenkainen's Polymorph

Until end of turn, target creature becomes a Dragon with base power and toughness 4/4 and gains flying. (It loses all other creature types.)

Blade of Selves

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

Fake Your Own Death

Until end of turn, target creature gets +2/+0 and gains "When this creature dies, return it to the battlefield tapped under its owner's control and you create a Treasure token." (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Djinni Windseer

Flying
When Djinni Windseer enters the battlefield, roll a d20.
1—9 | Scry 1.
10—19 | Scry 2.
20 | Scry 3.

Whack

This spell costs {3} less to cast if it targets a white creature.
Target creature gets -4/-4 until end of turn.

Nimbleclaw Adept

Bigby's Hand — {T}: Untap two other target permanents. Activate only as a sorcery and only once each turn.

Black Dragon Gate

Black Dragon Gate enters the battlefield tapped.
As Black Dragon Gate enters the battlefield, choose a color other than black.
{T}: Add {B} or one mana of the chosen color.

Griptide

Put target creature on top of its owner's library.

Split the Party

Choose target player. Return half the creatures they control to their owner's hand, rounded up.

Incriminate

Choose two target creatures controlled by the same player. That player sacrifices one of them.

Yuan-Ti Fang-Blade

Deathtouch
Whenever Yuan-Ti Fang-Blade deals combat damage to a player, venture into the dungeon. (Enter the first room or advance to the next room.)

Precipitous Drop

Enchant creature
When Precipitous Drop enters the battlefield, venture into the dungeon. (Enter the first room or advance to the next room.)
Enchanted creature gets -2/-2. It gets -5/-5 instead as long as you've completed a dungeon.

Void Snare

Return target nonland permanent to its owner's hand.

Dream Fracture

Counter target spell. Its controller draws a card.
Draw a card.

Tragic Fall

Target creature gets -3/-3 until end of turn.
Hellbent — That creature gets -13/-13 until end of turn instead if you have no cards in hand.

Devour Intellect

Target opponent discards a card. If mana from a Treasure was spent to cast this spell, instead that player reveals their hand, you choose a nonland card from it, then that player discards that card.

Archway Commons

Archway Commons enters the battlefield tapped.
When Archway Commons enters the battlefield, sacrifice it unless you pay {1}.
{T}: Add one mana of any color.

Guild Thief

Whenever Guild Thief deals combat damage to a player, put a +1/+1 counter on it.
Cunning Action — {3}{U}: Guild Thief can't be blocked this turn.

Shambling Ghast

When Shambling Ghast dies, choose one —
• Brave the Stench — Target creature an opponent controls gets -1/-1 until end of turn.
• Search the Body — Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Void Shatter

Devoid (This card has no color.)
Counter target spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Nightsnare

Target opponent reveals their hand. You may choose a nonland card from it. If you do, that player discards that card. If you don't, that player discards two cards.

Public Enemy

Enchant creature
All creatures attack enchanted creature's controller each combat if able.
When enchanted creature dies, draw a card.

Waterfront District

Waterfront District enters the battlefield tapped.
{T}: Add {U} or {B}.
{2}{U}{B}, {T}, Sacrifice Waterfront District: Draw a card.

Cancel

Haunting Echoes

Exile all cards from target player's graveyard other than basic land cards. For each card exiled this way, search that player's library for all cards with the same name as that card and exile them. Then that player shuffles.

Zhentarim Bandit

Whenever Zhentarim Bandit attacks, you may pay 1 life. If you do, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Sage-Eye Avengers

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever Sage-Eye Avengers attacks, you may return target creature to its owner's hand if its power is less than Sage-Eye Avengers's power.

Stoic Rebuttal

Metalcraft — This spell costs {1} less to cast if you control three or more artifacts.
Counter target spell.

Eccentric Apprentice

Flying
When Eccentric Apprentice enters the battlefield, venture into the dungeon. (Enter the first room or advance to the next room.)
At the beginning of combat on your turn, if you've completed a dungeon, up to one target creature becomes a Bird with base power and toughness 1/1 and flying until end of turn.

You Find the Villains' Lair

Choose one —
• Foil Their Scheme — Counter target spell.
• Learn Their Secrets — Draw two cards, then discard two cards.

Unholy Hunger

Destroy target creature.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, you gain 2 life.

Contact Other Plane

Roll a d20.
1—9 | Draw two cards.
10—19 | Scry 2, then draw two cards.
20 | Scry 3, then draw three cards.

Murder

Omnispell Adept

{2}{U}, {T}: You may cast an instant or sorcery spell from your hand without paying its mana cost.

Hive of the Eye Tyrant

If you control two or more other lands, Hive of the Eye Tyrant enters the battlefield tapped.
{T}: Add {B}.
{3}{B}: Until end of turn, Hive of the Eye Tyrant becomes a 3/3 black Beholder creature with menace and "Whenever this creature attacks, exile target card from defending player's graveyard." It's still a land.

Check for Traps

Target opponent reveals their hand. You choose a nonland card from it. Exile that card. If an instant card or a card with flash is exiled this way, they lose 1 life. Otherwise, you lose 1 life.

Sky Diamond

Sky Diamond enters the battlefield tapped.
{T}: Add {U}.

Suspicious Bookcase

Defender
{3}, {T}: Target creature can't be blocked this turn.

You See a Guard Approach

Choose one —
• Distract the Guard — Tap target creature.
• Hide — Target creature you control gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Arcane Signet

Fates' Reversal

Return up to one target creature card from your graveyard to your hand. Venture into the dungeon. (Enter the first room or advance to the next room.)

Pixie Guide

Flying
Grant an Advantage — If you would roll one or more dice, instead roll that many dice plus one and ignore the lowest roll.

Drider

Reach
Whenever Drider deals combat damage to a player, create a 2/1 black Spider creature token with menace and reach.

Swamp

Tasha, the Witch Queen

Whenever you cast a spell you don't own, create a 3/3 black Demon creature token.
+1: Draw a card. For each opponent, exile up to one target instant or sorcery card from that player's graveyard and put a page counter on it.
−3: You may cast a spell from among cards in exile with page counters on them without paying its mana cost.
Tasha, the Witch Queen can be your commander.

Grim Bounty

Destroy target creature or planeswalker. Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

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.

Noble's Purse

Noble's Purse enters the battlefield tapped and with three coin counters on it.
{T}, Remove a coin counter from Noble's Purse: Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Reckoner Shakedown

Target opponent reveals their hand. You may choose a nonland card from it. If you do, that player discards that card. If you don't, put two +1/+1 counters on a creature or Vehicle you control.

Mystic Redaction

At the beginning of your upkeep, scry 1.
Whenever you discard a card, each opponent mills two cards. (They put the top two cards of their library into their graveyard.)

Demogorgon's Clutches

Target opponent discards two cards, mills two cards, and loses 2 life. (To mill a card, a player puts the top card of their library into their graveyard.)

Thieves' Tools

When Thieves' Tools enters the battlefield, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
Equipped creature can't be blocked as long as its power is 3 or less.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Negate

Myrkul's Edict

Roll a d20.
1—9 | Choose an opponent. That player sacrifices a creature.
10—19 | Each opponent sacrifices a creature.
20 | Each opponent sacrifices a creature with the greatest power among creatures that player controls.

Tavern Swindler

{T}, Pay 3 life: Flip a coin. If you win the flip, you gain 6 life.

Scion of Stygia

Flash
Cone of Cold — When Scion of Stygia enters the battlefield, choose target creature an opponent controls, then roll a d20.
1—9 | Tap that creature.
10—20 | Tap that creature. It doesn't untap during its controller's next untap step.

Welcome to the Fold

Madness {X}{U}{U} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)
Gain control of target creature if its toughness is 2 or less. If this spell's madness cost was paid, instead gain control of that creature if its toughness is X or less.