Wizard's Rockets

Wizard's Rockets enters tapped.
{X}, {T}, Sacrifice Wizard's Rockets: Add X mana in any combination of colors.
When Wizard's Rockets is put into a graveyard from the battlefield, draw a card.

Goblin Anarchomancer

Each spell you cast that's red or green costs {1} less to cast.

Have

Thousand-Year Elixir

You may activate abilities of creatures you control as though those creatures had haste.
{1}, {T}: Untap target creature.

Wildest Dreams

Return X target cards from your graveyard to your hand. Exile Wildest Dreams.

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.

Magmaquake

Magmaquake deals X damage to each creature without flying and each planeswalker.

Horizon Stone

If you would lose unspent mana, that mana becomes colorless instead.

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.

Exponential Growth

Until end of turn, double target creature's power X times.

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.

Pest Infestation

Destroy up to X target artifacts and/or enchantments. Create twice X 1/1 black and green Pest creature tokens with "When this creature dies, you gain 1 life."

Getting

Nature's Chosen

Enchant creature you control
{0}: Untap enchanted creature. Activate only during your turn and only once each turn.
Tap enchanted creature: Untap target artifact, creature, or land. Activate only if enchanted creature is white and untapped and only once each turn.

Lifeblood Hydra

Trample
Lifeblood Hydra enters with X +1/+1 counters on it.
When Lifeblood Hydra dies, you gain life and draw cards equal to its power.

Gargos, Vicious Watcher

Vigilance
Hydra spells you cast cost {4} less to cast.
Whenever a creature you control becomes the target of a spell, Gargos, Vicious Watcher fights up to one target creature you don't control.

Clan Defiance

Choose one or more —
• Clan Defiance deals X damage to target creature with flying.
• Clan Defiance deals X damage to target creature without flying.
• Clan Defiance deals X damage to target player or planeswalker.

Saryth, the Viper's Fang

Other tapped creatures you control have deathtouch.
Other untapped creatures you control have hexproof.
{1}, {T}: Untap another target creature or land you control.

Apocalypse Hydra

Apocalypse Hydra enters with X +1/+1 counters on it. If X is 5 or more, it enters with an additional X +1/+1 counters on it.
{1}{R}, Remove a +1/+1 counter from Apocalypse Hydra: It deals 1 damage to any target.

Starstorm

Starstorm deals X damage to each creature.
Cycling {3} ({3}, Discard this card: Draw a card.)

Street Spasm

Street Spasm deals X damage to target creature without flying you don't control.
Overload {X}{X}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Kodama's Reach

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Cultivate

Magus of the Candelabra

Broodlord

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Brood Telepathy — When Broodlord enters, distribute X +1/+1 counters among any number of other target creatures you control.

Patriar's Seal

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

Nexos

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

Steelbane Hydra

Steelbane Hydra enters with X +1/+1 counters on it.
{2}{G}, Remove a +1/+1 counter from Steelbane Hydra: Destroy target artifact or enchantment.

Stony Strength

Put a +1/+1 counter on target creature you control. Untap that creature.

Commune with Lava

Exile the top X cards of your library. Until the end of your next turn, you may play those cards.

Tervigon

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Trample
Spawn Termagants — Whenever Tervigon deals combat damage to a player, create that many 1/1 green Tyranid creature tokens.

Sporocyst

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Defender
Spore Chimney — When Sporocyst enters, search your library for up to X basic land cards, put them onto the battlefield tapped, then shuffle.

Goblin Offensive

War Cadence

{X}{R}: This turn, creatures can't block unless their controller pays {X} for each blocking creature they control.

Shatterskull, the Hammer Pass

As Shatterskull, the Hammer Pass enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {R}.

Shatterskull Smashing

Shatterskull Smashing deals X damage divided as you choose among up to two target creatures and/or planeswalkers. If X is 6 or more, Shatterskull Smashing deals twice X damage divided as you choose among them instead.

Shatterskull Smashing // Shatterskull, the Hammer Pass

Song of Totentanz

Create X 1/1 black Rat creature tokens with "This creature can't block." Creatures you control gain haste until end of turn.

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}.

Kessig Wolf Run

{T}: Add {C}.
{X}{R}{G}, {T}: Target creature gets +X/+0 and gains trample until end of turn.

Seeker of Skybreak

Tempt with Vengeance

Tempting offer — Create X 1/1 red Elemental creature tokens with haste. Each opponent may create X 1/1 red Elemental creature tokens with haste. For each opponent who does, create X 1/1 red Elemental creature tokens with haste.

Quest for Renewal

Whenever a creature you control becomes tapped, you may put a quest counter on Quest for Renewal.
As long as there are four or more quest counters on Quest for Renewal, untap all creatures you control during each other player's untap step.

Weird Harvest

Each player may search their library for up to X creature cards, reveal those cards, put them into their hand, then shuffle.

Hell to Pay

Hell to Pay deals X damage to target creature. Create a number of tapped Treasure tokens equal to the amount of excess damage dealt to that creature this way.

Fireball

This spell costs {1} more to cast for each target beyond the first.
Fireball deals X damage divided evenly, rounded down, among any number of targets.

Rolling Earthquake

Rolling Earthquake deals X damage to each creature without horsemanship and each player.

Sting, the Glinting Dagger

Equipped creature gets +1/+1 and has haste.
At the beginning of each combat, untap equipped creature.
Equipped creature has first strike as long as it's blocking or blocked by a Goblin or Orc.
Equip {2}

Kozilek's Command

Choose two —
• Target player creates X 0/1 colorless Eldrazi Spawn creature tokens with "Sacrifice this creature: Add {C}."
• Target player scries X, then draws a card.
• Exile target creature with mana value X or less.
• Exile up to X target cards from graveyards.

Goldvein Hydra

Vigilance, trample, haste
Goldvein Hydra enters with X +1/+1 counters on it.
When Goldvein Hydra dies, create a number of tapped Treasure tokens equal to its power.

Upwelling

Players don't lose unspent mana as steps and phases end.

Rampant Growth

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

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.

Exocrine

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Bio-plasmic Barrage — When Exocrine enters, it deals X damage to each player and each other creature.

Astral Cornucopia

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

Mishra's Command

Choose two —
• Choose target player. They may discard up to X cards. Then they draw a card for each card discarded this way.
• This spell deals X damage to target creature.
• This spell deals X damage to target planeswalker.
• Target creature gets +X/+0 and gains haste until end of turn.

Meltdown

Destroy each artifact with mana value X or less.

Nahiri's Lithoforming

Sacrifice X lands. For each land sacrificed this way, draw a card. You may play X additional lands this turn. Lands you control enter tapped this turn.

Tyvar's Stand

Target creature you control gets +X/+X and gains hexproof and indestructible until end of turn. (A creature with hexproof and indestructible can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

By Force

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.

Screamer-Killer

Trample
Bio-Plasmic Scream — Whenever you cast a creature spell with mana value 5 or greater, Screamer-Killer deals 5 damage to any target.

Klauth's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Breathe Flame — Klauth's Will deals X damage to each creature without flying.
• Smash Relics — Destroy up to X target artifacts and/or enchantments.

Reap the Past

Return X cards at random from your graveyard to your hand. Exile Reap the Past.

Devil's Play

Devil's Play deals X damage to any target.
Flashback {X}{R}{R}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Helix Pinnacle

Shroud (This enchantment can't be the target of spells or abilities.)
{X}: Put X tower counters on Helix Pinnacle.
At the beginning of your upkeep, if there are 100 or more tower counters on Helix Pinnacle, you win the game.

Uncage the Menagerie

Search your library for up to X creature cards with different names that each have mana value X, reveal them, put them into your hand, then shuffle.

Arena of Glory

Arena of Glory enters tapped unless you control a Mountain.
{T}: Add {R}.
{R}, {T}, Exert Arena of Glory: Add {R}{R}. If that mana is spent on a creature spell, it gains haste until end of turn. (An exerted permanent won't untap during your next untap step.)

Treasure Vault

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

Enshrined Memories

Reveal the top X cards of your library. Put all creature cards revealed this way into your hand and the rest on the bottom of your library in any order.

Rampaging Yao Guai

Vigilance, trample
Rampaging Yao Guai enters with X +1/+1 counters on it.
When Rampaging Yao Guai enters, destroy any number of target artifacts and/or enchantments with total mana value X or less.

Crackle with Power

Crackle with Power deals five times X damage to each of up to X targets.

Worldsoul's Rage

Worldsoul's Rage deals X damage to any target. Put up to X land cards from your hand and/or graveyard onto the battlefield tapped.

Burst of Strength

Put a +1/+1 counter on target creature and untap it.

Emerald Charm

Choose one —
• Untap target permanent.
• Destroy target non-Aura enchantment.
• Target creature loses flying until end of turn.

Hooded Hydra

Hooded Hydra enters with X +1/+1 counters on it.
When Hooded Hydra dies, create a 1/1 green Snake creature token for each +1/+1 counter on it.
Morph {3}{G}{G}
As Hooded Hydra is turned face up, put five +1/+1 counters on it.

Aberrant

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Trample
Heavy Power Hammer — Whenever Aberrant deals combat damage to a player, destroy target artifact or enchantment that player controls.

Blast Zone

Blast Zone enters with a charge counter on it.
{T}: Add {C}.
{X}{X}, {T}: Put X charge counters on Blast Zone.
{3}, {T}, Sacrifice Blast Zone: Destroy each nonland permanent with mana value equal to the number of charge counters on Blast Zone.

Inspiring Call

Draw a card for each creature you control with a +1/+1 counter on it. Those creatures gain indestructible until end of turn. (Damage and effects that say "destroy" don't destroy them.)

Fault Line

Fault Line deals X damage to each creature without flying and each player.

Up the Beanstalk

When Up the Beanstalk enters and whenever you cast a spell with mana value 5 or greater, draw a card.

Rosheen Meanderer

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

New Frontiers

Each player may search their library for up to X basic land cards and put them onto the battlefield tapped. Then each player who searched their library this way shuffles.

Gelatinous Genesis

Earthquake

Earthquake deals X damage to each creature without flying and each player.

Scryb Ranger

Flash
Flying, protection from blue
Return a Forest you control to its owner's hand: Untap target creature. Activate only once each turn.

Termagant Swarm

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Death Frenzy — When Termagant Swarm dies, create a number of 1/1 green Tyranid creature tokens equal to Termagant Swarm's power.

Magewright's Stone

{1}, {T}: Untap target creature that has an activated ability with {T} in its cost.

Instill Energy

Enchant creature
Enchanted creature can attack as though it had haste.
{0}: Untap enchanted creature. Activate only during your turn and only once each turn.

Capricopian

Capricopian enters with X +1/+1 counters on it.
{2}: Put a +1/+1 counter on Capricopian, then you may reselect which player Capricopian is attacking. Only the player Capricopian is attacking may activate this ability and only during the declare attackers step. (It can't attack its controller.)

Awaken the Woods

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

Quirion Ranger

Return a Forest you control to its owner's hand: Untap target creature. Activate only once each turn.

Gift of the Viper

Put a +1/+1 counter, a reach counter, and a deathtouch counter on target creature. Untap it.

Runadi, Behemoth Caller

Whenever you cast a creature spell with mana value 5 or greater, that creature enters with X additional +1/+1 counters on it, where X is its mana value minus 4.
Creatures you control with three or more +1/+1 counters on them have haste.
{T}: Add {G}.

Rosheen, Roaring Prophet

When Rosheen, Roaring Prophet enters, 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}.