Fading 5 (This creature enters the battlefield with five fade counters on it. At the beginning of your upkeep, remove a fade counter from it. If you can't, sacrifice it.)

{1}, Remove a fade counter from Ancient Hydra: It deals 1 damage to any target.

Protection from white and from black

Whenever you cast a creature spell, put a +1/+1 counter on Animar, Soul of Elements.

Creature spells you cast cost {1} less to cast for each +1/+1 counter on Animar.

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.

Balduvian Hydra enters the battlefield with X +1/+0 counters on it.

Remove a +1/+0 counter from Balduvian Hydra: Prevent the next 1 damage that would be dealt to Balduvian Hydra this turn.

{R}{R}{R}: Put a +1/+0 counter on Balduvian Hydra. Activate only during your upkeep.

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.

Attacking creatures you control have deathtouch.

{1}{G}, {T}: Choose one --

• Put a +1/+1 counter on target creature.

• Bow of Nylea deals 2 damage to target creature with flying.

• You gain 3 life.

• Put up to four target cards from your graveyard on the bottom of your library in any order.

When Bristling Hydra enters the battlefield, you get {E}{E}{E} (three energy counters).

Pay {E}{E}{E}: Put a +1/+1 counter on Bristling Hydra. It gains hexproof until end of turn.

{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.

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.

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.

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

Whenever a player casts a spell, you may put a +1/+1 counter on Forgotten Ancient.

At the beginning of your upkeep, you may move any number of +1/+1 counters from Forgotten Ancient onto other creatures.

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.

Deathtouch

When God-Eternal Rhonas enters the battlefield, double the power of each other creature you control until end of turn. Those creatures gain vigilance until end of turn.

When God-Eternal Rhonas dies or is put into exile from the battlefield, you may put it into its owner's library third from the top.

Evolve (Whenever a creature enters the battlefield under your control, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)

{T}: Add {G} for each +1/+1 counter on Gyre Sage.

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.

Trample

Embalm {3}{G} ({3}{G}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a white Zombie Snake Hydra with no mana cost. Embalm only as a sorcery.)

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.

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.

Trample

Whenever Ilharg, the Raze-Boar attacks, you may put a creature card from your hand onto the battlefield tapped and attacking. Return that creature to your hand at the beginning of the next end step.

When Ilharg, the Raze-Boar dies or is put into exile from the battlefield, you may put it into its owner's library third from the top.

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

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.

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.

{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.

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.

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.

Partner with Toothy, Imaginary Friend (When this creature enters the battlefield, target player may put Toothy into their hand from their library, then shuffle.)

If one or more counters would be put on a permanent your team controls, that many plus one of each of those kinds of counters are put on that permanent instead.

{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.

Vigilance, reach, trample

Ramunap Hydra gets +1/+1 as long as you control a Desert.

Ramunap Hydra gets +1/+1 as long as there is a Desert card in your graveyard.

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

For each 1 damage that would be dealt to Rock Hydra, if it has a +1/+1 counter on it, remove a +1/+1 counter from it and prevent that 1 damage.

{R}: Prevent the next 1 damage that would be dealt to Rock Hydra this turn.

{R}{R}{R}: Put a +1/+1 counter on Rock Hydra. Activate only during your upkeep.

{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.

{T}: Untap target creature.

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

{1}{R}, Remove a +1/+1 counter from Spitting Hydra: It deals 1 damage to target creature.

Defender (This creature can't attack.)

Whenever Sprouting Phytohydra is dealt damage, you may create a token that's a copy of Sprouting Phytohydra.

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.

Trample

If damage would be dealt to another creature you control, prevent that damage. Put a +1/+1 counter on that creature for each 1 damage prevented this way.

When Vigor is put into a graveyard from anywhere, shuffle it into its owner's library.