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}, Pay 1 life, Sacrifice Arid Mesa: Search your library for a Mountain or Plains card, put it onto the battlefield, then shuffle.

Creatures you control have hexproof. (They can't be the targets of spells or abilities your opponents control.)

{1}{G}: Regenerate target creature.

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.)

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

{4}{R}{G}: Atarka Monument becomes a 4/4 red and green Dragon artifact creature with flying until end of turn.

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.

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

Flying

{T}: Add one mana of any color.

{T}, Pay 1 life, Sacrifice Bloodstained Mire: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

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.)

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

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

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

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

Copperline Gorge enters the battlefield tapped unless you control two or fewer other lands.

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

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.

Enchant player

Whenever a creature attacks enchanted player, put a +1/+1 counter on it.

Destroy target artifact, target creature, target enchantment, and target land. (You can't cast this spell unless you have legal choices for all its targets.)

+1: Look at the top card of your library. If it's a creature card, you may reveal it and put it into your hand.

-2: Target creature you control fights another target creature.

-7: You get an emblem with "Creatures you control have double strike, trample, hexproof, and haste."

As Door of Destinies enters the battlefield, choose a creature type.

Whenever you cast a spell of the chosen type, put a charge counter on Door of Destinies.

Creatures you control of the chosen type get +1/+1 for each charge counter on Door of Destinies.

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.

Green spells you cast cost {1} less to cast.

{G}, Sacrifice a creature: Reveal cards from the top of your library until you reveal a creature card. Put that card into your hand and the rest on the bottom of your library in a random order.

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

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

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

({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}.)

As Game Trail enters the battlefield, you may reveal a Mountain or Forest card from your hand. If you don't, Game Trail enters the battlefield tapped.

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

Create X X/X green Ooze creature tokens.

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 {R} or {G}.

{R}{G}, {T}, Sacrifice Gruul Cluestone: Draw a card.

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

{R}{G}: Gruul Keyrune becomes a 3/2 red and green Beast artifact creature with trample until end of turn.

{1}, {T}: Add {R}{G}.

Gruul Turf enters the battlefield tapped.

When Gruul Turf enters the battlefield, return a land you control to its owner's hand.

{T}: Add {R}{G}.

Creatures you control have haste.

{2}{R}, {T}, Sacrifice a land: Create a 3/3 colorless Golem enchantment artifact creature token.

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

Heroes' Bane enters the battlefield 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.

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.

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

Trample

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.

As an additional cost to cast this spell, sacrifice a creature.

Draw cards equal to the sacrificed creature's power.

{T}: Add {G}.

Trample

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

As Metallic Mimic enters the battlefield, choose a creature type.

Metallic Mimic is the chosen type in addition to its other types.

Each other creature you control of the chosen type enters the battlefield with an additional +1/+1 counter on it.

This spell can't be countered.

Haste, protection from blue

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

{T}, Pay 1 life, Sacrifice Misty Rainforest: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

{1}{R}{R}: Put a +1/+1 counter on Molten Hydra.

{T}, Remove all +1/+1 counters from Molten Hydra: It deals damage to any target equal to the number of +1/+1 counters removed this way.

Hideaway 4 (When this land enters the battlefield, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)

Mosswort Bridge enters the battlefield tapped.

{T}: Add {G}.

{G}, {T}: You may play the exiled card without paying its mana cost if creatures you control have total power 10 or greater.

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

({T}: Add {R}.)

Tribute 6 (As this creature enters the battlefield, an opponent of your choice may put six +1/+1 counters on it.)

When Nessian Wilds Ravager enters the battlefield, if tribute wasn't paid, you may have Nessian Wilds Ravager fight another target creature. (Each deals damage equal to its power to the other.)

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.

Oran-Rief, the Vastwood enters the battlefield tapped.

{T}: Add {G}.

{T}: Put a +1/+1 counter on each green creature that entered the battlefield this turn.

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

If damage would be dealt to Phyrexian Hydra, prevent that damage. Put a -1/-1 counter on Phyrexian Hydra for each 1 damage prevented this way.

{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.

Whenever you cast a creature spell, create a 3/3 green Beast creature token.

Whenever you cast a noncreature spell, put three +1/+1 counters on target creature you control.

Landfall -- Whenever a land enters the battlefield under your control, you gain 3 life.

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.

Rootbound Crag enters the battlefield tapped unless you control a Mountain or a Forest.

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

{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.

{T}, Pay 1 life, Sacrifice Scalding Tarn: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

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.

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

Strive -- This spell costs {1}{G} more to cast for each target beyond the first.

Choose any number of target creatures. Double the number of +1/+1 counters on each of them.

({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.

Multikicker {1} (You may pay an additional {1} any number of times as you cast this spell.)

Choose target creature, then choose another target creature for each time this spell was kicked. Put X +1/+1 counters on each of them.

Ulasht, the Hate Seed enters the battlefield with a +1/+1 counter on it for each other red creature you control and a +1/+1 counter on it for each other green creature you control.

{1}, Remove a +1/+1 counter from Ulasht: Choose one --

• Ulasht deals 1 damage to target creature.

• Create a 1/1 green Saproling creature token.

Reach

Ulvenwald Hydra's power and toughness are each equal to the number of lands you control.

When Ulvenwald Hydra enters the battlefield, you may search your library for a land card, put it onto the battlefield tapped, then shuffle.

As Urza's Incubator enters the battlefield, choose a creature type.

Creature spells of the chosen type cost {2} less to cast.

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

When Vastwood Hydra dies, you may distribute a number of +1/+1 counters equal to the number of +1/+1 counters on Vastwood Hydra among any number of creatures you control.

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.

+1: Add X mana in any combination of {R} and/or {G}, where X is the number of creatures you control.

0: Create a 2/2 red and green Satyr creature token with haste.

-6: Exile the top seven cards of your library. You may put any number of creature and/or land cards from among them onto the battlefield.