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 . If you do, return Hormagaunt Horde from your graveyard to your hand.

Exile X target creature cards from your graveyard. For each card exiled this way, create a token that's a copy of that card, except it's a 4/4 black Zombie.

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.)

As Hydradoodle enters the battlefield, roll X six-sided dice. Hydradoodle enters the battlefield with a number of +1/+1 counters on it equal to the total of those results.

Reach, trample

Iceberg enters the battlefield with X ice counters on it.

: Put an ice counter on Iceberg.

Remove an ice counter from Iceberg: Add .

Ceremorphosis — When Illithid Harvester enters the battlefield, turn any number of target tapped nontoken creatures face down. They're 2/2 Horror creatures.

Return each creature card with mana value X from your graveyard to the battlefield.

Target player mills X cards. If this spell was cast from a graveyard, that player mills twice that many cards instead.

Flashback (You may cast this card from your graveyard for its flashback cost. Then exile it.)

You may pay rather than pay this spell's mana cost.

If the cost was paid, you draw three cards, then an opponent creates two Treasure tokens and they scry 2. If that cost wasn't paid, you draw X cards.

(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)

When Invasion of Ikoria enters the battlefield, search your library and/or graveyard for a non-Human creature card with mana value X or less and put it onto the battlefield. If you search your library this way, shuffle.

Choose one —

• Draw X cards.

• Invoke the Firemind deals X damage to any target.

When Jadelight Spelunker enters the battlefield, it explores X times. (To have it explore, reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on that creature, then put the card back or put it into your graveyard.)

(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.

As long as Kaervek's Torch is on the stack, spells that target it cost more to cast.

Kaervek's Torch deals X damage to any target.

Look at the top seven cards of your library. Put up to X artifact and/or creature cards with mana value 3 or less from among them onto the battlefield. Put the rest on the bottom of your library in a random order.

For each creature, its controller sacrifices it unless they pay X life.

Knickknack Ouphe enters the battlefield with X +1/+1 counters on it.

When Knickknack Ouphe enters the battlefield, reveal the top X cards of your library. You may put any number of Aura cards with mana value X or less from among them onto the battlefield. Then put all cards revealed this way that weren't put onto the battlefield on the bottom of your library in a random order.

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.

Lavalanche deals X damage to target player or planeswalker and each creature that player or that planeswalker's controller controls.

Trample

Lifeblood Hydra enters the battlefield with X +1/+1 counters on it.

When Lifeblood Hydra dies, you gain life and draw cards equal to its power.

Light Up the Night deals X damage to any target. It deals X plus 1 damage instead if that target is a creature or planeswalker.

Flashback—, Remove X loyalty counters from among planeswalkers you control. If you cast this spell this way, X can't be 0. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Mill X cards. Target player loses 2 life for each creature card put into your graveyard this way.

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.

This spell costs less to cast if it targets a creature whose controller has eight or more cards in their graveyard.

Gain control of target creature with mana value X.

Target creature gets +X/+X until end of turn. Create a 1/1 green and white Citizen creature token.

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.

Tap X target artifacts, creatures, and/or lands. You lose X life.

As an additional cost to cast this spell, you may exile any number of green cards from your hand. This spell costs less to cast for each card exiled this way.

Choose target creature with mana value less than X. Search your library for a creature card with the same name as that creature, put it onto the battlefield tapped, then shuffle.

As an additional cost to cast this spell, you may exile any number of red cards from your hand. This spell costs less to cast for each card exiled this way.

Exile the top X cards of your library. You may play up to two of those cards until the end of your next turn.

When March of the Canonized enters the battlefield, create X 1/1 white Vampire creature tokens with lifelink.

At the beginning of your upkeep, if your devotion to white and black is seven or greater, create a 4/3 white and black Vampire Demon creature token with flying.

As an additional cost to cast this spell, you may exile any number of black cards from your hand. This spell costs less to cast for each card exiled this way.

March of Wretched Sorrow deals X damage to target creature or planeswalker and you gain X life.

Gain control of X target creatures and/or planeswalkers.

Destroy each artifact with mana value X or less.

Meteor Shower deals X plus 1 damage divided as you choose among any number of targets.

Exile X target creature cards from your graveyard. For each creature card exiled this way, create a 2/2 black Zombie creature token.

Each opponent reveals cards from the top of their library until they reveal X land cards, then puts all cards revealed this way into their graveyard. X can't be 0.

Draw X cards.

Look at target player's hand and choose X cards from it. That player discards those cards.

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.

Destroy target artifact or enchantment with mana value X. It can't be regenerated. You gain X life.

If X is 1, scry 1, then draw a card.

If X is 2, you may choose a player. They return a creature they control to its owner's hand.

If X is 3, create a 4/4 blue and red Elemental creature token.

If X is 4 or more, do all of the above.

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

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.

Flying

Nimbus Swimmer enters the battlefield with X +1/+1 counters on it.

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.

Choose one —

• Search your library for up to X land cards, reveal them, put them into your hand, then shuffle.

• Nylea's Intervention deals twice X damage to each creature with flying.

Trample

Ochre Jelly enters the battlefield with X +1/+1 counters on it.

Split — When Ochre Jelly dies, if it had two or more +1/+1 counters on it, create a token that's a copy of it at the beginning of the next end step. The token enters the battlefield with half that many +1/+1 counters on it, rounded down.

When you cast this spell, reveal cards from the top of your library until you reveal X creature cards. Put all creature cards revealed this way into your graveyard, then put the rest on the bottom of your library in a random order.

Old Stickfingers's power and toughness are each equal to the number of creature cards in your graveyard.

X target creatures can't be blocked this turn. Until end of turn, those creatures gain "Whenever this creature deals combat damage to a player, draw a card."

Flying, trample

When Orcus, Prince of Undeath enters the battlefield, choose one —

• Each other creature gets -X/-X until end of turn. You lose X life.

• Return up to X target creature cards with total mana value X or less from your graveyard to the battlefield. They gain haste until end of turn.