Ertai's Scorn

This spell costs {U} less to cast if an opponent cast two or more spells this turn.
Counter target spell.

Graveyard Shift

This spell has flash as long as there are five or more mana values among cards in your graveyard.
Return target creature card from your graveyard to the battlefield.

Go for the Throat

Island

Cut Down

Destroy target creature with total power and toughness 5 or less.

Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Dissipate

Counter target spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Restless Reef

Restless Reef enters tapped.
{T}: Add {U} or {B}.
{2}{U}{B}: Until end of turn, Restless Reef becomes a 4/4 blue and black Shark creature with deathtouch. It's still a land.
Whenever Restless Reef attacks, target player mills four cards.

Bleed Dry

Target creature gets -13/-13 until end of turn. If that creature would die this turn, exile it instead.

Assimilate Essence

Counter target creature or battle spell unless its controller pays {4}. If they do, you incubate 2. (Create an Incubator token with two +1/+1 counters on it and "{2}: Transform this artifact." It transforms into a 0/0 Phyrexian artifact creature.)

Overwhelming Remorse

This spell costs {1} less to cast for each creature card in your graveyard.
Exile target creature or planeswalker.

Faerie Fencing

Target creature gets -X/-X until end of turn. That creature gets an additional -3/-3 until end of turn if you controlled a Faerie as you cast this spell.

Infernal Grasp

Destroy target creature. You lose 2 life.

Defabricate

Choose one —
• Counter target artifact or enchantment spell. If a spell is countered this way, exile it instead of putting it into its owner's graveyard.
• Counter target activated or triggered ability.

Disruption Protocol

As an additional cost to cast this spell, tap an untapped artifact you control or pay {1}.
Counter target spell.

Urza's Rebuff

Choose one —
• Counter target spell.
• Tap up to two target creatures.

Sheoldred's Edict

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

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.

Syncopate

Counter target spell unless its controller pays {X}. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Frantic Firebolt

Frantic Firebolt deals X damage to target creature, where X is 2 plus the number of cards in your graveyard that are instant cards, sorcery cards, and/or have an Adventure.

Insectile Aberration

Delver of Secrets

At the beginning of your upkeep, look at the top card of your library. You may reveal that card. If an instant or sorcery card is revealed this way, transform Delver of Secrets.

Delver of Secrets // Insectile Aberration

Moment of Defiance

Target creature gets +2/+1 and gains lifelink until end of turn.
Draw a card.

Curate

Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Draw a card.

Fungal Fortitude

Flash
Enchant creature
Enchanted creature gets +2/+0.
When enchanted creature dies, return it to the battlefield tapped under its owner's control.

Change the Equation

Choose one —
• Counter target spell with mana value 2 or less.
• Counter target red or green spell with mana value 6 or less.

Galvanize

Galvanize deals 3 damage to target creature. If you've drawn two or more cards this turn, Galvanize deals 5 damage to that creature instead.

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.")

Murder

Planar Incision

Exile target artifact or creature, then return it to the battlefield under its owner's control with a +1/+1 counter on it.

Whack

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

Maestros Theater

When Maestros Theater enters, sacrifice it. When you do, search your library for a basic Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle and you gain 1 life.

Essence Scatter

Blood Pact

Target player draws two cards and loses 2 life.

Abrade

Choose one —
• Abrade deals 3 damage to target creature.
• Destroy target artifact.

Not Dead After All

Until end of turn, target creature you control gains "When this creature dies, return it to the battlefield tapped under its owner's control, then create a Wicked Role token attached to it." (Enchanted creature gets +1/+1. When this Aura is put into a graveyard, each opponent loses 1 life.)

Electric Revelation

As an additional cost to cast this spell, discard a card.
Draw two cards.
Flashback {3}{R} (You may cast this card from your graveyard for its flashback cost and any additional costs. Then exile it.)

Tainted Indulgence

Draw two cards. Then discard a card unless there are five or more mana values among cards in your graveyard.

Shipwreck Marsh

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

Big Score

As an additional cost to cast this spell, discard a card.
Draw two cards and create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Hero's Downfall

Devious Cover-Up

Counter target spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard. You may shuffle up to four target cards from your graveyard into your library.

Swamp

Disdainful Stroke

Counter target spell with mana value 4 or greater.

Wash Away

Cleave {1}{U}{U} (You may cast this spell for its cleave cost. If you do, remove the words in square brackets.)
Counter target spell [that wasn't cast from its owner's hand].

Return to Action

Until end of turn, target creature gets +1/+0 and gains lifelink and "When this creature dies, return it to the battlefield tapped under its owner's control."

Out of Air

This spell costs {2} less to cast if it targets a creature spell.
Counter target spell.

Quick Study

Defossilize

Return target creature card from your graveyard to the battlefield. That creature explores, then it explores again. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on that creature, then put the card back or put it into your graveyard. Then repeat this process.)

Tolarian Terror

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)

Shatter the Oath

Destroy target creature or enchantment. Create a Wicked Role token attached to up to one target creature you control. (If you control another Role on it, put that one into the graveyard. Enchanted creature gets +1/+1. When this Aura is put into a graveyard, each opponent loses 1 life.)

Demon's Due

Scry 2, then draw two cards. You lose 2 life.

Negate

Merciless Repurposing

Exile target creature. Incubate 3. (Create an Incubator token with three +1/+1 counters on it and "{2}: Transform this artifact." It transforms into a 0/0 Phyrexian artifact creature.)

Rogues' Gallery

For each color, return up to one target creature card of that color from your graveyard to your hand.

Vat Emergence

Put target creature card from a graveyard onto the battlefield under your control. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Contaminated Aquifer

({T}: Add {U} or {B}.)
Contaminated Aquifer enters tapped.

Volatile Fault

{T}: Add {C}.
{1}, {T}, Sacrifice Volatile Fault: Destroy target nonbasic land an opponent controls. That player may search their library for a basic land card, put it onto the battlefield, then shuffle. You create a Treasure token.

No One Left Behind

This spell costs {3} less to cast if it targets a creature card with mana value 3 or less.
Return target creature card from your graveyard to the battlefield.