Ertai's Scorn

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

Flowstone Surge

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. Shivan Reef deals 1 damage to you.

Breath of Fury

Enchant creature you control
When enchanted creature deals combat damage to a player, sacrifice it and attach Breath of Fury to a creature you control. If you do, untap all creatures you control and after this phase, there is an additional combat phase.

Obelisk of Urd

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
As Obelisk of Urd enters the battlefield, choose a creature type.
Creatures you control of the chosen type get +2/+2.

Izzet Boilerworks

Izzet Boilerworks enters the battlefield tapped.
When Izzet Boilerworks enters the battlefield, return a land you control to its owner's hand.
{T}: Add {U}{R}.

Mana Echoes

Whenever a creature enters the battlefield, you may add an amount of {C} equal to the number of creatures you control that share a creature type with it.

Thran Dynamo

Temple of Epiphany

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

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.

Fellwar Stone

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

Sulfur Falls

Sulfur Falls enters the battlefield tapped unless you control an Island or a Mountain.
{T}: Add {U} or {R}.

Confound

Counter target spell that targets a creature.
Draw a card.

Ashnod's Altar

Quest for the Goblin Lord

Whenever a Goblin enters the battlefield under your control, you may put a quest counter on Quest for the Goblin Lord.
As long as Quest for the Goblin Lord has five or more quest counters on it, creatures you control get +2/+0.

Frostboil Snarl

As Frostboil Snarl enters the battlefield, you may reveal an Island or Mountain card from your hand. If you don't, Frostboil Snarl enters the battlefield tapped.
{T}: Add {U} or {R}.

Command Tower

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

The Immortal Sun

Players can't activate planeswalkers' loyalty abilities.
At the beginning of your draw step, draw an additional card.
Spells you cast cost {1} less to cast.
Creatures you control get +1/+1.

Mountain

Goblin Bombardment

Sacrifice a creature: Goblin Bombardment deals 1 damage to any target.

Strixhaven Stadium

{T}: Add {C}. Put a point counter on Strixhaven Stadium.
Whenever a creature deals combat damage to you, remove a point counter from Strixhaven Stadium.
Whenever a creature you control deals combat damage to an opponent, put a point counter on Strixhaven Stadium. Then if it has ten or more point counters on it, remove them all and that player loses the game.

Reconnaissance Mission

Whenever a creature you control deals combat damage to a player, you may draw a card.
Cycling {2} ({2}, Discard this card: Draw a card.)

Shark Typhoon

Whenever you cast a noncreature spell, create an X/X blue Shark creature token with flying, where X is that spell's mana value.
Cycling {X}{1}{U} ({X}{1}{U}, Discard this card: Draw a card.)
When you cycle Shark Typhoon, create an X/X blue Shark creature token with flying.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Sorcerer Class

(Gain the next level as a sorcery to add its ability.)
When Sorcerer Class enters the battlefield, draw two cards, then discard two cards.
{U}{R}: Level 2
Creatures you control have "{T}: Add {U} or {R}. Spend this mana only to cast an instant or sorcery spell or to gain a Class level."
{3}{U}{R}: Level 3
Whenever you cast an instant or sorcery spell, that spell deals damage to each opponent equal to the number of instant and sorcery spells you've cast this turn.

Shared Animosity

Whenever a creature you control attacks, it gets +1/+0 until end of turn for each other attacking creature that shares a creature type with it.

Skullclamp

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

Izzet Signet

Audacious Swap

Casualty 2 (As you cast this spell, you may sacrifice a creature with power 2 or greater. When you do, copy this spell and you may choose a new target for the copy.)
The owner of target nonenchantment permanent shuffles it into their library, then exiles the top card of their library. If it's a land card, they put it onto the battlefield. Otherwise, they may cast it without paying its mana cost.

Throne of the God-Pharaoh

At the beginning of your end step, each opponent loses life equal to the number of tapped creatures you control.

Dolmen Gate

Prevent all combat damage that would be dealt to attacking creatures you control.

Myriad Landscape

Myriad Landscape enters the battlefield 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.

Sol Ring

Bident of Thassa

Whenever a creature you control deals combat damage to a player, you may draw a card.
{1}{U}, {T}: Creatures your opponents control attack this turn if able.

Boggart Shenanigans

Whenever another Goblin you control is put into a graveyard from the battlefield, you may have Boggart Shenanigans deal 1 damage to target player or planeswalker.

Ovika, Enigma Goliath

Flying
Ward—{3}, Pay 3 life.
Whenever you cast a noncreature spell, create X 1/1 red Phyrexian Goblin creature tokens, where X is the mana value of that spell. They gain haste until end of turn.

Exotic Orchard

Reliquary Tower

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

Rob the Archives

Casualty 1 (As you cast this spell, you may sacrifice a creature with power 1 or greater. When you do, copy this spell.)
Exile the top two cards of your library. You may play those cards this turn.

Rooftop Nuisance

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.)
Tap target creature. It doesn't untap during its controller's next untap step.
Draw a card.

Ferocity of the Wilds

Attacking non-Human creatures you control get +1/+0 and have trample.

Berserkers' Onslaught

Attacking creatures you control have double strike.

Goblin War Drums

Creatures you control have menace. (They can't be blocked except by two or more creatures.)

Hall of Triumph

As Hall of Triumph enters the battlefield, choose a color.
Creatures you control of the chosen color get +1/+1.

Thought Vessel

Impact Tremors

Whenever a creature enters the battlefield under your control, Impact Tremors deals 1 damage to each opponent.

Lightning Greaves

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

Cavalcade of Calamity

Whenever a creature you control with power 1 or less attacks, Cavalcade of Calamity deals 1 damage to the player or planeswalker that creature is attacking.

One with the Multiverse

You may look at the top card of your library any time.
You may play lands and cast spells from the top of your library.
Once during each of your turns, you may cast a spell from your hand or the top of your library without paying its mana cost.

Island

Flawless Forgery

Casualty 3 (As you cast this spell, you may sacrifice a creature with power 3 or greater. When you do, copy this spell and you may choose a new target for the copy.)
Exile target instant or sorcery card from an opponent's graveyard. Copy that card. You may cast the copy without paying its mana cost.

Delay

Counter target spell. If the spell is countered this way, exile it with three time counters on it instead of putting it into its owner's graveyard. If it doesn't have suspend, it gains suspend. (At the beginning of its owner's upkeep, they remove a time counter. When the last is removed, they may play it without paying its mana cost. If it's a creature, it has haste.)

Eldrazi Monument

Creatures you control get +1/+1 and have flying and indestructible.
At the beginning of your upkeep, sacrifice a creature. If you can't, sacrifice Eldrazi Monument.

Levitation

Talisman of Creativity

{T}: Add {C}.
{T}: Add {U} or {R}. Talisman of Creativity deals 1 damage to you.

Disallow

Counter target spell, activated ability, or triggered ability. (Mana abilities can't be targeted.)

Sunbird's Invocation

Whenever you cast a spell from your hand, reveal the top X cards of your library, where X is that spell's mana value. You may cast a spell with mana value X or less from among cards revealed this way without paying its mana cost. Put the rest on the bottom of your library in a random order.

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.

Brazen Cannonade

Whenever an attacking creature you control dies, Brazen Cannonade deals 2 damage to each opponent.
Raid — At the beginning of your postcombat main phase, if you attacked with a creature this turn, exile the top card of your library. Until end of combat on your next turn, you may play that card.

Insidious Will

Choose one —
• Counter target spell.
• You may choose new targets for target spell.
• Copy target instant or sorcery spell. You may choose new targets for the copy.

Goblin War Strike

Goblin War Strike deals damage to target player or planeswalker equal to the number of Goblins you control.

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice Hedron Archive: Draw two cards.

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.

Midnight Clock

{T}: Add {U}.
{2}{U}: Put an hour counter on Midnight Clock.
At the beginning of each upkeep, put an hour counter on Midnight Clock.
When the twelfth hour counter is put on Midnight Clock, shuffle your hand and graveyard into your library, then draw seven cards. Exile Midnight Clock.

Training Center

Training Center enters the battlefield tapped unless you have two or more opponents.
{T}: Add {U} or {R}.

Mechanized Warfare

If a red or artifact source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 1 instead.

Popular Entertainer

Commander creatures you own have "Whenever one or more creatures you control deal combat damage to a player, goad target creature that player controls." (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)

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.")

Bane's Contingency

Counter target spell. If that spell targets a commander you control, instead counter that spell, scry 2, then draw a card.

Arcane Signet

Heraldic Banner

As Heraldic Banner enters the battlefield, choose a color.
Creatures you control of the chosen color get +1/+0.
{T}: Add one mana of the chosen color.

Raid Bombardment

Whenever a creature you control with power 2 or less attacks, Raid Bombardment deals 1 damage to the player or planeswalker that creature is attacking.