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.)

Trample

Heavy Power Hammer -- Whenever Aberrant deals combat damage to a player, destroy target artifact or enchantment that player controls.

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.

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.

This spell costs {2} less to cast if it targets a legendary creature you control.

Target creature you control deals damage equal to twice its power to target creature or planeswalker you don't control.

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.

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

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.

Creatures you control have base power and toughness X/X until end of turn.

Choose one --

• Search your library for a basic land card, reveal it, put it into your hand, then shuffle.

• Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

({T}: Add {R} or {G}.)

Cinder Glade enters the battlefield tapped unless you control two or more basic lands.

Proclamator Hailer -- Each creature you control gets +1/+1 for each +1/+1 counter on it.

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.

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

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.

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

You have no maximum hand size.

{T}: Add one mana of any color.

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

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}.

Sacrifice a land. Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle. If you control a creature with power 4 or greater, instead search your library for up to three basic land cards, put them onto the battlefield tapped, then shuffle.

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

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.

Whenever Fleet Swallower attacks, target player mills half their library, rounded up.

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

Frontier Bivouac enters the battlefield tapped.

{T}: Add {G}, {U}, or {R}.

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.

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.

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.

{T}: Add two mana in any combination of colors. Spend this mana only to cast creature spells or activate abilities of a creature or creature card.

Whenever you cast a creature spell with power 5 or greater, put a +1/+1 counter on Gwenna, Eyes of Gaea and untap it.

Hangarback Walker enters the battlefield with X +1/+1 counters on it.

When Hangarback Walker dies, create a 1/1 colorless Thopter artifact creature token with flying for each +1/+1 counter on Hangarback Walker.

{1}, {T}: Put a +1/+1 counter on Hangarback Walker.

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

Ward {2}

At the beginning of your precombat main phase, add {G}{G}.

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.)

Green

{X}{X}{G}: Monstrosity X. (If this creature isn't monstrous, put X +1/+1 counters on it and it becomes monstrous.)

When Hydra Broodmaster becomes monstrous, create X X/X green Hydra creature tokens.

Enchant creature

When Hydra's Growth enters the battlefield, put a +1/+1 counter on enchanted creature.

At the beginning of your upkeep, double the number of +1/+1 counters on enchanted creature.

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

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.

Mutate {3}{R/G}{U}{U} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)

Flying, trample

Whenever this creature mutates, exile cards from the top of your library until you exile a nonland permanent card. Put that card onto the battlefield or into your hand.

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.)

If a creature would deal combat damage to Ironscale Hydra, prevent that damage and put a +1/+1 counter on Ironscale Hydra.

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

(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.

Trample

Kalonian Hydra enters the battlefield with four +1/+1 counters on it.

Whenever Kalonian Hydra attacks, double the number of +1/+1 counters on each creature you control.

{T}: Add {C}.

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

Whenever a creature with power 4 or greater enters the battlefield under your control, draw a card.

-1: Untap target permanent.

Reach

Modified creatures you control have trample. (Equipment, Auras you control, and counters are modifications.)

Whenever a modified creature you control deals combat damage to a player, search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

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.

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.)

Trample

Whenever a player casts a spell, put a +1/+1 counter on Managorger Hydra.

Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Cycling {2} ({2}, Discard this card: Draw a card.)

Flash

Indestructible

When Mithril Coat enters the battlefield, attach it to target legendary creature you control.

Equipped creature has indestructible.

Equip {3}

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

Myriad Landscape enters the battlefield tapped.

{T}: Add {C}.

{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

As Neverwinter Hydra enters the battlefield, roll X d6. It enters with a number of +1/+1 counters on it equal to the total of those results.

Trample

Ward {4} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {4}.)

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

Flying

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

Path of Ancestry enters the battlefield tapped.

{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

If one or more tokens would be created, twice that many of those tokens are created instead.

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

{T}: Add {C}.

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

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

If damage would be dealt to Protean Hydra, prevent that damage and remove that many +1/+1 counters from it.

Whenever a +1/+1 counter is removed from Protean Hydra, put two +1/+1 counters on it at the beginning of the next end step.

Vigilance, trample

Rampaging Yao Guai enters the battlefield with X +1/+1 counters on it.

When Rampaging Yao Guai enters the battlefield, destroy any number of target artifacts and/or enchantments with total mana value X or less.

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

Trample

When Regal Behemoth enters the battlefield, you become the monarch.

Whenever you tap a land for mana while you're the monarch, add an additional one mana of any color.

You have no maximum hand size.

{T}: Add {C}.

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.

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

Whenever you cast a creature spell with mana value 5 or greater, that creature enters the battlefield 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}.

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.

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.

As Shatterskull, the Hammer Pass enters the battlefield, you may pay 3 life. If you don't, it enters the battlefield tapped.

{T}: Add {R}.

Flying, haste

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

{T}: Add {C}{C}.

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.

Sulfur Falls enters the battlefield tapped unless you control an Island or a Mountain.

{T}: Add {U} or {R}.

Swiftwater Cliffs enters the battlefield tapped.

When Swiftwater Cliffs enters the battlefield, you gain 1 life.

{T}: Add {U} or {R}.

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

Flying

The Goose Mother enters the battlefield with X +1/+1 counters on it.

When The Goose Mother enters the battlefield, create half X Food tokens, rounded up.

Whenever The Goose Mother attacks, you may sacrifice a Food. If you do, draw a card.

Whenever a creature you control leaves the battlefield, if it had counters on it, put those counters on The Ozolith.

At the beginning of combat on your turn, if The Ozolith has counters on it, you may move all counters from The Ozolith onto target creature.

Thornwood Falls enters the battlefield tapped.

When Thornwood Falls enters the battlefield, you gain 1 life.

{T}: Add {G} or {U}.

Thriving Bluff enters the battlefield tapped.

As Thriving Bluff enters the battlefield, choose a color other than red.

{T}: Add {R} or one mana of the chosen color.

Thriving Grove enters the battlefield tapped.

As Thriving Grove enters the battlefield, choose a color other than green.

{T}: Add {G} or one mana of the chosen color.

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.

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.

As Unclaimed Territory enters the battlefield, choose a creature type.

{T}: Add {C}.

{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.

Trample

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

When Voracious Hydra enters the battlefield, choose one --

• Double the number of +1/+1 counters on Voracious Hydra.

• Voracious Hydra fights target creature you don't control.

Whenever a creature enters the battlefield under your control, it deals damage equal to its power to any target.

Reach

When Whiptongue Hydra enters the battlefield, destroy all creatures with flying. Put a +1/+1 counter on Whiptongue Hydra for each creature destroyed this way.

Flying, haste

The Will of the Hive Mind -- Other creatures you control with counters on them have flying and haste.

Reach

Wren's Run Hydra enters the battlefield with X +1/+1 counters on it.

Reinforce X--{X}{G}{G} ({X}{G}{G}, Discard this card: Put X +1/+1 counters on target creature.)

Indestructible

As long as your devotion to red and green is less than seven, Xenagos isn't a creature.

At the beginning of combat on your turn, another target creature you control gains haste and gets +X/+X until end of turn, where X is that creature's power.