Stolen by the Fae

Return target creature with mana value X to its owner's hand. You create X 1/1 blue Faerie creature tokens with flying.

Treasure Vault

{T}: Add {C}.
{X}{X}, {T}, Sacrifice Treasure Vault: Create X Treasure tokens.

Minamo, School at Water's Edge

{T}: Add {U}.
{U}, {T}: Untap target legendary permanent.

Stroke of Genius

Red Sun's Twilight

Destroy up to X target artifacts. If X is 5 or more, for each artifact destroyed this way, create a token that's a copy of it. Those tokens gain haste. Exile them at the beginning of the next end step.

Ashling, Flame Dancer

You don't lose unspent red mana as steps and phases end.
Magecraft — Whenever you cast or copy an instant or sorcery spell, discard a card, then draw a card. If this is the second time this ability has resolved this turn, Ashling, Flame Dancer deals 2 damage to each opponent and each creature they control. If it's the third time, add {R}{R}{R}{R}.

Birds of Paradise

Mountain

Karplusan Forest

{T}: Add {C}.
{T}: Add {R} or {G}. Karplusan Forest deals 1 damage to you.

Talisman of Curiosity

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

Double Vision

Whenever you cast your first instant or sorcery spell each turn, copy that spell. You may choose new targets for the copy.

Island

Drown in Dreams

Choose one. If you control a commander as you cast this spell, you may choose both.
• Target player draws X cards.
• Target player mills twice X cards.

Nexos

Strategic Coordinator — Basic lands you control have "{T}: Add {C}{C}. Spend this mana only on costs that contain {X}."

Patriar's Seal

{T}: Add one mana of any color.
{1}, {T}: Untap target legendary creature you control.

Unbound Flourishing

Whenever you cast a permanent spell with a mana cost that contains {X}, double the value of X.
Whenever you cast an instant or sorcery spell or activate an ability, if that spell's mana cost or that ability's activation cost contains {X}, copy that spell or ability. You may choose new targets for the copy.

Ketria Triome

({T}: Add {G}, {U}, or {R}.)
Ketria Triome enters the battlefield tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

Frontier Bivouac

Frontier Bivouac enters the battlefield tapped.
{T}: Add {G}, {U}, or {R}.

Open the Way

X can't be greater than the number of players in the game.
Reveal cards from the top of your library until you reveal X land cards. Put those land cards onto the battlefield tapped and the rest on the bottom of your library in a random order.

Stonecoil Serpent

Reach, trample, protection from multicolored
Stonecoil Serpent enters the battlefield with X +1/+1 counters on it.

Doppelgang

For each of X target permanents, create X tokens that are copies of that permanent.

Swarm Intelligence

Whenever you cast an instant or sorcery spell, you may copy that spell. You may choose new targets for the copy.

Arcane Signet

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

Mana Bloom

Mana Bloom enters the battlefield with X charge counters on it.
Remove a charge counter from Mana Bloom: Add one mana of any color. Activate only once each turn.
At the beginning of your upkeep, if Mana Bloom has no charge counters on it, return it to its owner's hand.

Sol Ring

Elementalist's Palette

Whenever you cast a spell with {X} in its mana cost, put two charge counters on Elementalist's Palette.
{T}: Add one mana of any color.
{T}: Add {C} for each charge counter on Elementalist's Palette. Spend this mana only on costs that contain {X}.

Spiteful Banditry

When Spiteful Banditry enters the battlefield, it deals X damage to each creature.
Whenever one or more creatures your opponents control die, you create a Treasure token. This ability triggers only once each turn.

Rosheen Meanderer

{T}: Add {C}{C}{C}{C}. Spend this mana only on costs that contain {X}.

Invigorating Hot Spring

Invigorating Hot Spring enters the battlefield with four +1/+1 counters on it.
Modified creatures you control have haste. (Equipment, Auras you control, and counters are modifications.)
Remove a +1/+1 counter from Invigorating Hot Spring: Put a +1/+1 counter on target creature you control. Activate only as a sorcery and only once each turn.

Exotic Orchard

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

Slime Molding

Purphoros's Intervention

Choose one —
• Create an X/1 red Elemental creature token with trample and haste. Sacrifice it at the beginning of the next end step.
• Purphoros's Intervention deals twice X damage to target creature or planeswalker.

Kiora's Follower

Storm-Kiln Artist

Storm-Kiln Artist gets +1/+0 for each artifact you control.
Magecraft — Whenever you cast or copy an instant or sorcery spell, create a Treasure token.

Rejuvenating Springs

Rejuvenating Springs enters the battlefield tapped unless you have two or more opponents.
{T}: Add {G} or {U}.

Ingenious Prodigy

Skulk (This creature can't be blocked by creatures with greater power.)
Ingenious Prodigy enters the battlefield with X +1/+1 counters on it.
At the beginning of your upkeep, if Ingenious Prodigy has one or more +1/+1 counters on it, you may remove a +1/+1 counter from it. If you do, draw a card.

Magus Lucea Kane

Spiritual Leader — At the beginning of combat on your turn, put a +1/+1 counter on target creature.
Psychic Stimulus — {T}: Add {C}{C}. When you next cast a spell with {X} in its mana cost or activate an ability with {X} in its activation cost this turn, copy that spell or ability. You may choose new targets for the copy. (A copy of a permanent spell becomes a token.)

Curse of the Swine

Exile X target creatures. For each creature exiled this way, its controller creates a 2/2 green Boar creature token.

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Wooded Foothills

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

Wurmcalling

Buyback {2}{G} (You may pay an additional {2}{G} as you cast this spell. If you do, put this card into your hand as it resolves.)
Create an X/X green Wurm creature token.

Steam Vents

({T}: Add {U} or {R}.)
As Steam Vents enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Kiora, Behemoth Beckoner

Whenever a creature with power 4 or greater enters the battlefield under your control, draw a card.
−1: Untap target permanent.

Gandalf the Grey

Whenever you cast an instant or sorcery spell, choose one that hasn't been chosen —
• You may tap or untap target permanent.
• Gandalf the Grey deals 3 damage to each opponent.
• Copy target instant or sorcery spell you control. You may choose new targets for the copy.
• Put Gandalf on top of its owner's library.

Blue Sun's Twilight

Gain control of target creature with mana value X or less. If X is 5 or more, create a token that's a copy of that creature.

Mystical Tutor

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

Yavimaya Coast

{T}: Add {C}.
{T}: Add {G} or {U}. Yavimaya Coast deals 1 damage to you.

Bloom Tender

{T}: For each color among permanents you control, add one mana of that color.

Astral Cornucopia

Astral Cornucopia enters the battlefield with X charge counters on it.
{T}: Choose a color. Add one mana of that color for each charge counter on Astral Cornucopia.

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Talisman of Creativity

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

Narset's Reversal

Copy target instant or sorcery spell, then return it to its owner's hand. You may choose new targets for the copy.

Shivan Reef

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

Rosheen, Roaring Prophet

When Rosheen, Roaring Prophet enters the battlefield, mill six cards. You may put a card with {X} in its mana cost from among them into your hand.
{T}: Reveal any number of cards with {X} in their mana cost in your hand. Add {C}{C} for each card revealed this way. Spend this mana only on costs that contain {X}.

Fanatic of Rhonas

{T}: Add {G}.
Ferocious — {T}: Add {G}{G}{G}{G}. Activate only if you control a creature with power 4 or greater.
Eternalize {2}{G}{G} ({2}{G}{G}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a 4/4 black Zombie Snake Druid with no mana cost. Eternalize only as a sorcery.)

Forest

Deekah, Fractal Theorist

Magecraft — Whenever you cast or copy an instant or sorcery spell, create a 0/0 green and blue Fractal creature token. Put X +1/+1 counters on it, where X is that spell's mana value.
{3}{U}: Target creature token can't be blocked this turn.

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

Incubation Druid

{T}: Add one mana of any type that a land you control could produce. If Incubation Druid has a +1/+1 counter on it, add three mana of that type instead.
{3}{G}{G}: Adapt 3. (If this creature has no +1/+1 counters on it, put three +1/+1 counters on it.)

Twinning Staff

If you would copy a spell one or more times, instead copy it that many times plus an additional time. You may choose new targets for the additional copy.
{7}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

Animist's Awakening

Reveal the top X cards of your library. Put all land cards from among them onto the battlefield tapped and the rest on the bottom of your library in a random order.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, untap those lands.

Stomping Ground

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

Command Tower

Breeding Pool

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

Kami of Whispered Hopes

If one or more +1/+1 counters would be put on a permanent you control, that many plus one +1/+1 counters are put on that permanent instead.
{T}: Add X mana of any one color, where X is Kami of Whispered Hopes's power.

Gelatinous Genesis

Thassa's Intervention

Choose one —
• Look at the top X cards of your library. Put up to two of them into your hand and the rest on the bottom of your library in a random order.
• Counter target spell unless its controller pays twice {X}.

Gyre Sage

Evolve (Whenever a creature enters the battlefield under your control, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)
{T}: Add {G} for each +1/+1 counter on Gyre Sage.

Electrodominance

Electrodominance deals X damage to any target. You may cast a spell with mana value X or less from your hand without paying its mana cost.

Archmage Emeritus

Magecraft — Whenever you cast or copy an instant or sorcery spell, draw a card.

Repulsive Mutation

Put X +1/+1 counters on target creature you control. Then counter up to one target spell unless its controller pays mana equal to the greatest power among creatures you control.

Counterspell

Comet Storm

Multikicker {1} (You may pay an additional {1} any number of times as you cast this spell.)
Choose any target, then choose another target for each time this spell was kicked. Comet Storm deals X damage to each of them.

Cinder Glade

({T}: Add {R} or {G}.)
Cinder Glade enters the battlefield tapped unless you control two or more basic lands.

Mana Geyser

Add {R} for each tapped land your opponents control.

Awaken the Woods

Create X 1/1 green Forest Dryad land creature tokens. (They're affected by summoning sickness.)

Talisman of Impulse

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

Hydroid Krasis

When you cast this spell, you gain half X life and draw half X cards. Round down each time.
Flying, trample
Hydroid Krasis enters the battlefield with X +1/+1 counters on it.

Storm King's Thunder

When you next cast an instant or sorcery spell this turn, copy that spell X times. You may choose new targets for the copies.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.