Stream of Consciousness

Target player shuffles up to four target cards from their graveyard into their library.

Mountain

Sunder from Within

Disrupting Shoal

You may exile a blue card with mana value X from your hand rather than pay this spell's mana cost.
Counter target spell if its mana value is X.

Death of a Thousand Stings

Target player loses 1 life and you gain 1 life.
At the beginning of your upkeep, if you have more cards in hand than each opponent, you may return Death of a Thousand Stings from your graveyard to your hand.

Glacial Ray

Glacial Ray deals 2 damage to any target.
Splice onto Arcane {1}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Cranial Extraction

Choose a nonland card name. Search target player's graveyard, hand, and library for all cards with that name and exile them. Then that player shuffles.

Cormela, Glamour Thief

Haste
{1}, {T}: Add {U}{B}{R}. Spend this mana only to cast instant and/or sorcery spells.
When Cormela, Glamour Thief dies, return up to one target instant or sorcery card from your graveyard to your hand.

Island

Crack the Earth

Each player sacrifices a permanent of their choice.

Spiraling Embers

Spiraling Embers deals damage to any target equal to the number of cards in your hand.

Aura Barbs

Each enchantment deals 2 damage to its controller, then each Aura attached to a creature deals 2 damage to the creature it's attached to.

Part the Veil

Return all creatures you control to their owner's hand.

Torrent of Stone

Torrent of Stone deals 4 damage to target creature.
Splice onto Arcane—Sacrifice two Mountains. (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Footsteps of the Goryo

Return target creature card from your graveyard to the battlefield. Sacrifice that creature at the beginning of the next end step.

Eye of Nowhere

Return target permanent to its owner's hand.

Eerie Procession

Search your library for an Arcane card, reveal that card, put it into your hand, then shuffle.

Petals of Insight

Look at the top three cards of your library. You may put those cards on the bottom of your library in any order. If you do, return Petals of Insight to its owner's hand. Otherwise, draw three cards.

Heed the Mists

Mill a card, then draw cards equal to the milled card's mana value.

Reach Through Mists

Ire of Kaminari

Ire of Kaminari deals damage to any target equal to the number of Arcane cards in your graveyard.

Ribbons of the Reikai

Reweave

Target permanent's controller sacrifices it. If the player does, they reveal cards from the top of their library until they reveal a permanent card that shares a card type with the sacrificed permanent, put that card onto the battlefield, then shuffle.
Splice onto Arcane {2}{U}{U} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Swamp

Hideous Laughter

All creatures get -2/-2 until end of turn.
Splice onto Arcane {3}{B}{B} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Shifting Borders

Exchange control of two target lands.
Splice onto Arcane {3}{U} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Overblaze

Each time target permanent would deal damage to a permanent or player this turn, it deals double that damage to that permanent or player instead.
Splice onto Arcane {2}{R}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Ideas Unbound

Draw three cards. Discard three cards at the beginning of the next end step.

Murmurs from Beyond

Reveal the top three cards of your library. An opponent chooses one of them. Put that card into your graveyard and the rest into your hand.

Terramorphic Expanse

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

First Volley

First Volley deals 1 damage to target creature and 1 damage to that creature's controller.

Blazing Shoal

You may exile a red card with mana value X from your hand rather than pay this spell's mana cost.
Target creature gets +X/+0 until end of turn.

Unnatural Speed

Target creature gains haste until end of turn.

Devouring Rage

As an additional cost to cast this spell, you may sacrifice any number of Spirits.
Target creature gets +3/+0 until end of turn. For each Spirit sacrificed this way, that creature gets an additional +3/+0 until end of turn.

Devouring Greed

As an additional cost to cast this spell, you may sacrifice any number of Spirits.
Target player loses 2 life plus 2 life for each Spirit sacrificed this way. You gain that much life.

Through the Breach

You may put a creature card from your hand onto the battlefield. That creature gains haste. Sacrifice that creature at the beginning of the next end step.
Splice onto Arcane {2}{R}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Lava Spike

Lava Spike deals 3 damage to target player or planeswalker.

Cut the Earthly Bond

Return target enchanted permanent to its owner's hand.

Rend Flesh

Sift Through Sands

Draw two cards, then discard a card.
If you've cast a spell named Peer Through Depths and a spell named Reach Through Mists this turn, you may search your library for a card named The Unspeakable, put it onto the battlefield, then shuffle.

Crushing Pain

Crushing Pain deals 6 damage to target creature that was dealt damage this turn.

Psychic Puppetry

You may tap or untap target permanent.
Splice onto Arcane {U} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Choice of Damnations

Target opponent chooses a number. You may have that player lose that much life. If you don't, that player sacrifices all but that many permanents of their choice.

Death Denied

Return X target creature cards from your graveyard to your hand.

Unearthly Blizzard

Up to three target creatures can't block this turn.

Evolving Wilds

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

Sink into Takenuma

Sweep — Return any number of Swamps you control to their owner's hand. Target player discards a card for each Swamp returned this way.

Lifted by Clouds

Target creature gains flying until end of turn.
Splice onto Arcane {1}{U} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Desperate Ritual

Add {R}{R}{R}.
Splice onto Arcane {1}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Dance of Shadows

Creatures you control get +1/+0 and gain fear until end of turn. (They can't be blocked except by artifact creatures and/or black creatures.)

Into the Fray

Target creature attacks this turn if able.
Splice onto Arcane {R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Goryo's Vengeance

Return target legendary creature card from your graveyard to the battlefield. That creature gains haste. Exile it at the beginning of the next end step.
Splice onto Arcane {2}{B} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Blind with Anger

Untap target nonlegendary creature and gain control of it until end of turn. That creature gains haste until end of turn.

Veil of Secrecy

Target creature gains shroud until end of turn and can't be blocked this turn. (A creature with shroud can't be the target of spells or abilities.)
Splice onto Arcane—Return a blue creature you control to its owner's hand. (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Peer Through Depths

Look at the top five cards of your library. You may reveal an instant or sorcery card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Sickening Shoal

You may exile a black card with mana value X from your hand rather than pay this spell's mana cost.
Target creature gets -X/-X until end of turn.

Barrel Down Sokenzan

Sweep — Return any number of Mountains you control to their owner's hand. Barrel Down Sokenzan deals damage to target creature equal to twice the number of Mountains returned this way.

Command Tower

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

Soulless Revival

Return target creature card from your graveyard to your hand.
Splice onto Arcane {1}{B} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Dampen Thought

Target player mills four cards.
Splice onto Arcane {1}{U} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Horobi's Whisper

If you control a Swamp, destroy target nonblack creature.
Splice onto Arcane—Exile four cards from your graveyard. (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Consuming Vortex

Return target creature to its owner's hand.
Splice onto Arcane {3}{U} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Three Tragedies

Strange Inversion

Switch target creature's power and toughness until end of turn.
Splice onto Arcane {1}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Call for Blood

As an additional cost to cast this spell, sacrifice a creature.
Target creature gets -X/-X until end of turn, where X is the sacrificed creature's power.

Gaze of Adamaro

Gaze of Adamaro deals damage to target player equal to the number of cards in that player's hand.

Pull Under

Target creature gets -5/-5 until end of turn.

Path of Anger's Flame

Creatures you control get +2/+0 until end of turn.

Swallowing Plague

Swallowing Plague deals X damage to target creature and you gain X life.

Waking Nightmare

Evermind

(Nonexistent mana costs can't be paid.)
Draw a card.
Splice onto Arcane {1}{U} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Toils of Night and Day

You may tap or untap target permanent, then you may tap or untap another target permanent.