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.

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}.

Apocalypse Hydra enters the battlefield with X +1/+1 counters on it. If X is 5 or more, it enters the battlefield 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.

Ravenous (This creature enters the battlefield 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 the battlefield, it deals X damage to each player and each other creature.

Flying Whenever Flameblast Dragon attacks, you may pay {X}{R}. If you do, Flameblast Dragon deals X damage to any target.

When you cast this spell, reveal the top X cards of your library. You may put a nonland permanent card with mana value X or less from among them onto the battlefield. Then shuffle the rest into your library. Genesis Hydra enters the battlefield with X +1/+1 counters on it.

Ravenous (This creature enters the battlefield with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.) Endless Swarm — Whenever a land enters the battlefield under your control, you may pay {2}{G}. If you do, return Hormagaunt Horde from your graveyard to your hand.

Hungering Hydra enters the battlefield with X +1/+1 counters on it. Hungering Hydra can't be blocked by more than one creature. Whenever Hungering Hydra is dealt damage, put that many +1/+1 counters on it. (It must survive the damage to get the counters.)

Kurbis, Harvest Celebrant enters the battlefield with a number of +1/+1 counters on it equal to the amount of mana spent to cast it. Remove a +1/+1 counter from Kurbis: Prevent all damage that would be dealt this turn to another target creature with a +1/+1 counter on it.

Magma Pummeler enters the battlefield with X +1/+1 counters on it. If damage would be dealt to Magma Pummeler while it has a +1/+1 counter on it, prevent that damage and remove that many +1/+1 counters from it. When one or more counters are removed from Magma Pummeler this way, it deals that much damage to any target.

Ravenous (This creature enters the battlefield with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.) Terror from the Deep — When Mawloc enters the battlefield, it fights up to one target creature an opponent controls. If that creature would die this turn, exile it instead.

This spell can't be countered. Haste, protection from blue Mistcutter Hydra enters the battlefield with X +1/+1 counters on it.

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

Trample If you tap a permanent for mana, it produces three times as much of that mana instead.

Primordial Hydra enters the battlefield with X +1/+1 counters on it. At the beginning of your upkeep, double the number of +1/+1 counters on Primordial Hydra. Primordial Hydra has trample as long as it has ten or more +1/+1 counters on it.

Ravenous Slime can't be blocked by creatures with power 2 or less. If a creature an opponent controls would die, instead exile it and put a number of +1/+1 counters equal to that creature's power on Ravenous Slime.

Double strike Savageborn Hydra enters the battlefield with X +1/+1 counters on it. {1}{R/G}: Put a +1/+1 counter on Savageborn Hydra. Activate only as a sorcery.

Whenever another creature enters the battlefield, its controller may draw a card if its power is greater than each other creature's power. {G}, {T}: Add X mana in any combination of colors, where X is the greatest power among creatures you control.

Flying, haste Shivan Devastator enters the battlefield with X +1/+1 counters on it.

Ravenous (This creature enters the battlefield 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 the battlefield, search your library for up to X basic land cards, put them onto the battlefield tapped, then shuffle.

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

Ravenous (This creature enters the battlefield with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.) Shieldwall — Sacrifice Tyrant Guard: Creatures you control with counters on them gain hexproof and indestructible until end of turn.

This spell can't be countered. {R/G}: Target spell can't be countered.

Trample, haste If you would put one or more counters on a permanent or player, put twice that many of each of those kinds of counters on that permanent or player instead. If an opponent would put one or more counters on a permanent or player, they put half that many of each of those kinds of counters on that permanent or player instead, rounded down.

{3}{R}{R}: Untap all creatures you control. After this main phase, there is an additional combat phase followed by an additional main phase. Activate only as a sorcery.

Whenever you put one or more counters on a permanent or player, All Will Be One deals that much damage to target opponent, creature an opponent controls, or planeswalker an opponent controls.

If one or more +1/+1 counters would be put on a creature you control, twice that many +1/+1 counters are put on that creature instead.

When Court of Garenbrig enters the battlefield, you become the monarch. At the beginning of your upkeep, distribute two +1/+1 counters among up to two target creatures. Then if you're the monarch, double the number of +1/+1 counters on each creature you control.

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead. If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

When Garruk's Uprising enters the battlefield, if you control a creature with power 4 or greater, draw a card. Creatures you control have trample. (They can deal excess combat damage to the player or planeswalker they're attacking.) Whenever a creature with power 4 or greater enters the battlefield under your control, draw a card.

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.

{1}{R}, Remove a +1/+1 counter or a charge counter from a permanent you control: Ion Storm deals 2 damage to any target.

Creature spells you control can't be countered. Nontoken creatures you control have riot. (They enter the battlefield with your choice of a +1/+1 counter or haste.)

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.

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.

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

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.

Permanents you control gain hexproof and indestructible until end of turn.

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

You may exile a green card with mana value X from your hand rather than pay this spell's mana cost. You gain X life.

Ravaging Blaze deals X damage to target creature. Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, Ravaging Blaze also deals X damage to that creature's controller.

Players can't gain life this turn. Damage can't be prevented this turn. Skullcrack deals 3 damage to target player or planeswalker.

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

{3}, {T}: Tap target creature you control and target creature of an opponent's choice they control. Those creatures fight each other. (Each deals damage equal to its power to the other.)

{T}: Add {G}. Channel — {1}{G}, Discard Boseiju, Who Endures: Destroy target artifact, enchantment, or nonbasic land an opponent controls. That player may search their library for a land card with a basic land type, put it onto the battlefield, then shuffle. This ability costs {1} less to activate for each legendary creature you control.

Boseiju, Who Shelters All enters the battlefield tapped. {T}, Pay 2 life: Add {C}. If that mana is spent on an instant or sorcery spell, that spell can't be countered.

Castle Garenbrig enters the battlefield tapped unless you control a Forest. {T}: Add {G}. {2}{G}{G}, {T}: Add six {G}. Spend this mana only to cast creature spells or activate abilities of creatures.

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

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

({T}: Add {G}.)

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

If you control two or more other lands, Lair of the Hydra enters the battlefield tapped. {T}: Add {G}. {X}{G}: Until end of turn, Lair of the Hydra becomes an X/X green Hydra creature. It's still a land. X can't be 0.

({T}: Add {R}.)

{T}: Add {C}. {2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Rockfall Vale enters the battlefield tapped unless you control two or more other lands. {T}: Add {R} or {G}.

Rootbound Crag enters the battlefield tapped unless you control a Mountain or a Forest. {T}: Add {R} or {G}.

({T}: Add {G}.) Sapseep Forest enters the battlefield tapped. {G}, {T}: You gain 1 life. Activate only if you control two or more green permanents.

Spire Garden enters the battlefield tapped unless you have two or more opponents. {T}: Add {R} or {G}.

({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.

{T}: Add {C}{C}. Activate only if you control five or more lands.

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

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

Banefire deals X damage to any target. If X is 5 or more, this spell can't be countered and the damage can't be prevented.

Bonfire of the Damned deals X damage to target player or planeswalker and each creature that player or that planeswalker's controller controls. Miracle {X}{R} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

Burn from Within deals X damage to any target. If a creature is dealt damage this way, it loses indestructible until end of turn. If that creature would die this turn, exile it instead.

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.

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

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.)

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.) Fanning the Flames deals X damage to any target.

Search your library and/or graveyard for a creature card with mana value X or less and put it onto the battlefield. If you search your library this way, shuffle. If X is 10 or more, creatures you control get +X/+X and gain haste until end of turn.

(You may cast a legendary sorcery only if you control a legendary creature or planeswalker.) Jaya's Immolating Inferno deals X damage to each of up to three targets.

Return X target cards with different mana values from your graveyard to your hand. If eight or more cards were returned to your hand this way, your life total becomes equal to your starting life total. Exile Long Rest.

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."

For each player, choose friend or foe. Each friend searches their library for a land card, puts it onto the battlefield tapped, then shuffles. Each foe sacrifices an artifact or enchantment they control.

Choose one — • Destroy target land. • Search your library for a land card, put that card onto the battlefield, then shuffle. Entwine {1}{G} (Choose both if you pay the entwine cost.)

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.

Red Sun's Zenith deals X damage to any target. If a creature dealt damage this way would die this turn, exile it instead. Shuffle Red Sun's Zenith into its owner's library.