This spell can't be countered.

You may have Altered Ego enter the battlefield as a copy of any creature on the battlefield, except it enters with X additional +1/+1 counters on it.

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.

{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.

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

Flying

{T}: Add one mana of any color.

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.)

Castle Garenbrig enters the battlefield tapped unless you control a Forest.

{T}: Add {G}.

{2}{G}{G}, {T}: Add six {G}. Spend this mana only to cast creature spells or activate abilities of creatures.

Choose one or more --

• Destroy target artifact.

• Destroy target creature.

• Destroy target enchantment.

• Destroy target land.

• Destroy target planeswalker.

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

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

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.

If you control a commander, you may cast this spell without paying its mana cost.

Exile target creature.

Dimir Aqueduct enters the battlefield tapped.

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

{T}: Add {U}{B}.

Dismal Backwater enters the battlefield tapped.

When Dismal Backwater enters the battlefield, you gain 1 life.

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

{T}: Add {G}.

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

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

Each opponent loses X life. You gain life equal to the life lost this way.

Draw X cards. If X is 10 or more, instead shuffle your graveyard into your library, draw X cards, untap up to five lands, and you have no maximum hand size for the rest of the game.

Exile Finale of Revelation.

({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}.)

Enchant creature

{U}: Tap enchanted creature.

{U}: Untap enchanted creature.

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.

Destroy each nonland permanent with mana value X or less.

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 three mana of any one color.

Golgari Rot Farm enters the battlefield tapped.

When Golgari Rot Farm enters the battlefield, return a land you control to its owner's hand.

{T}: Add {B}{G}.

Grakmaw, Skyclave Ravager enters the battlefield with three +1/+1 counters on it.

Whenever another creature you control dies, if it had a +1/+1 counter on it, put a +1/+1 counter on Grakmaw.

When Grakmaw dies, create an X/X black and green Hydra creature token, where X is the number of +1/+1 counters on Grakmaw.

At the beginning of combat on your turn, put a +1/+1 counter on target creature you control. Then if that creature has three or more +1/+1 counters on it, transform Hadana's Climb.

(Transforms from Hadana's Climb.)

{T}: Add one mana of any color.

{1}{G}{U}, {T}: Target creature you control gains flying and gets +X/+X until end of turn, where X is its power.

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.

Put five +1/+1 counters on target creature. If this spell was cast from a graveyard, put ten +1/+1 counters on that creature instead.

Flashback {5}{G}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

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}.)

Jungle Hollow enters the battlefield tapped.

When Jungle Hollow enters the battlefield, you gain 1 life.

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

{T}: Add {C}.

{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

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.

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)

Destroy target artifact or enchantment.

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.

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)

Equip {0}

{T}: Add {G}.

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

This spell can't be countered.

Haste, protection from blue

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

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.

+2: Scry 2.

0: Look at the top card of your library. If it's a land card or a creature card with mana value less than or equal to the number of loyalty counters on Nissa, Steward of Elements, you may put that card onto the battlefield.

-6: Untap up to two target lands you control. They become 5/5 Elemental creatures with flying and haste until end of turn. They're still lands.

{T}: Add {C}.

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

Indestructible

As long as your devotion to green is less than five, Nylea isn't a creature. (Each {G} in the mana costs of permanents you control counts toward your devotion to green.)

Other creatures you control have trample.

{3}{G}: Target creature gets +2/+2 until end of turn.

Opulent Palace enters the battlefield tapped.

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

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.

Enchant land

Whenever enchanted land is tapped for mana, its controller adds an additional {G}{G}.

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.

Choose two --

• Target player loses X life.

• Return target creature card with mana value X or less from your graveyard to the battlefield.

• Target creature gets -X/-X until end of turn.

• Up to X target creatures gain fear until end of turn. (They can't be blocked except by artifact creatures and/or black creatures.)

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

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.

Destroy target artifact or creature. It can't be regenerated.

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

You have no maximum hand size.

{T}: Add {C}.

Choose one --

• Destroy target artifact.

• Destroy target enchantment.

• Exile target card from a graveyard.

{T}: Add {C}.

{4}, {T}: Target creature can't be blocked this turn.

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

{1}{G}{U}: Put a +1/+1 counter on target creature you control.

Whenever one or more +1/+1 counters are put on a creature you control, put that many growth counters on Simic Ascendancy.

At the beginning of your upkeep, if Simic Ascendancy has twenty or more growth counters on it, you win the game.

Simic Growth Chamber enters the battlefield tapped.

When Simic Growth Chamber enters the battlefield, return a land you control to its owner's hand.

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

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

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.

Reach, trample, protection from multicolored

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

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)

Equip {1}

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

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

This spell costs {X} less to cast, where X is the greatest power among creatures you control.

{T}: Add {G}{G}. You gain 2 life.

Whenever a nontoken creature enters the battlefield under your control, put a +1/+1 counter on it and draw a card.

Thornwood Falls enters the battlefield tapped.

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

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

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

Repeat the following process X times. Each opponent loses 3 life unless that player sacrifices a nonland permanent or discards a card.

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.

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.

Target opponent exiles the top X cards of their library. You may cast any number of spells with mana value X or less from among them without paying their mana costs.

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.

{G}{U}, {T}: Double the number of each kind of counter on target artifact, creature, or land.

Deathtouch

{T}: Add two mana of any one color.

Whenever you cast a spell with {X} in its mana cost, create a 0/0 green Hydra creature token, then put X +1/+1 counters on it.

Whenever you tap a land for mana, add one mana of any type that land produced. (The types of mana are white, blue, black, red, green, and colorless.)

Whenever you cast a creature spell, draw a card.