Enchant land

When Abundant Growth enters the battlefield, draw a card.

Enchanted land has "{T}: Add one mana of any color."

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

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.

Target creature gets +X/+X until end of turn, where X is your devotion to green. (Each {G} in the mana costs of permanents you control counts toward your devotion to green.)

Haste

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

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

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

{T}, Remove a +1/+1 counter from Benevolent Hydra: Put a +1/+1 counter on another target creature you control.

Trample

Bioessence Hydra enters the battlefield with a +1/+1 counter on it for each loyalty counter on planeswalkers you control.

Whenever one or more loyalty counters are put on planeswalkers you control, put that many +1/+1 counters on Bioessence Hydra.

({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.

Trample

Domain -- Whenever Briar Hydra deals combat damage to a player, put X +1/+1 counters on target creature you control, where X is the number of basic land types among lands you control.

Capricopian enters the battlefield 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.)

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

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

Commercial District enters the battlefield tapped.

When Commercial District enters the battlefield, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

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.

Until end of turn, lands you control gain "{T}: Add one mana of any color."

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

As long as Domesticated Hydra is monstrous, it has trample.

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}.

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

Feral Hydra enters with X +1/+1 counters on it.

{3}: Put a +1/+1 counter on Feral Hydra. Any player may activate this ability.

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.

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

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.

Target creature gets +3/+3 until end of turn.

Enchant land

When Grafted Growth enters the battlefield, put a +1/+1 counter on target creature or Vehicle you control.

Enchanted land has "{T}: Add two mana of any one color."

Target creature gets +3/+3 until end of turn. It gets an additional +2/+2 until end of turn for each card named Growth Cycle in your graveyard.

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

Hedge Maze enters the battlefield tapped.

When Hedge Maze enters the battlefield, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Heroes' Bane enters with four +1/+1 counters on it.

{2}{G}{G}: Put X +1/+1 counters on Heroes' Bane, where X is its power.

Hooded Hydra enters the battlefield 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.

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.)

{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.

Whenever Hydra Omnivore deals combat damage to an opponent, it deals that much damage to each other opponent.

Enchant creature

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

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

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}.)

Trample

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

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

This spell costs {G} less to cast for each green creature you control.

Trample

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.

Lightning Bolt deals 3 damage to any target.

{T}: Add {G}.

{G}, {T}, Discard a card: Create a 1/1 green Elf Druid creature token named Llanowar Elves. It has "{T}: Add {G}."

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.

This spell can't be countered.

Haste, protection from blue

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

Target creature gets +4/+4 until end of turn.

Target creature gets +2/+0 until end of turn. Create a Monster Role token attached to it. (If you control another Role on it, put that one into the graveyard. Enchanted creature gets +1/+1 and has trample.)

Target creature gets +7/+7 until end of turn. Up to one other target creature blocks it this turn if able.

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

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

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}."

Trample

Landfall -- Whenever a land enters the battlefield under your control, put a +1/+1 counter on Oran-Rief Hydra. If that land is a Forest, put two +1/+1 counters on Oran-Rief Hydra instead.

Reach

{6}{W/P}: Transform Polukranos Reborn. Activate only as a sorcery. ({W/P} can be paid with either {W} or 2 life.)

Reach, lifelink

Whenever Polukranos, Engine of Ruin or another nontoken Hydra you control dies, create a 3/3 green and white Phyrexian Hydra creature token with reach and a 3/3 green and white Phyrexian Hydra creature token with lifelink.

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

When Polukranos, World Eater becomes monstrous, it deals X damage divided as you choose among any number of target creatures your opponents control. Each of those creatures deals damage equal to its power to Polukranos.

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.

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.

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

Rampant Rejuvenator enters the battlefield with two +1/+1 counters on it.

When Rampant Rejuvenator dies, search your library for up to X basic land cards, where X is Rampant Rejuvenator's power, put them onto the battlefield, then shuffle.

Ward {2}

As Roaming Throne enters the battlefield, choose a creature type.

Roaming Throne is the chosen type in addition to its other types.

If a triggered ability of another creature you control of the chosen type triggers, it triggers an additional time.

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

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.

Trample

Scourge of Skola Vale enters the battlefield with two +1/+1 counters on it.

{T}, Sacrifice another creature: Put a number of +1/+1 counters on Scourge of Skola Vale equal to the sacrificed creature's toughness.

Flying, haste

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

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

({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.

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.

({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.

Reach, trample, protection from multicolored

Stonecoil Serpent enters the battlefield with X +1/+1 counters on it.

When Stumpsquall Hydra enters the battlefield, distribute X +1/+1 counters among it and any number of commanders.

Target creature gets +2/+2 until end of turn. You may put a land card from your hand onto the battlefield.

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.

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

Thundering Falls enters the battlefield tapped.

When Thundering Falls enters the battlefield, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Target creature gets +4/+4 until end of 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.

Enchant land

Enchanted land has "{T}: Add one mana of any color."

Sacrifice Unbridled Growth: Draw a card.

At the beginning of each combat, double the power and toughness of each creature you control until end of turn.

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.

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.)