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.)

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.)

{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.

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.

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.

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.)

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

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.

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

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.

Clockwork Hydra enters the battlefield with four +1/+1 counters on it. Whenever Clockwork Hydra attacks or blocks, remove a +1/+1 counter from it. If you do, Clockwork Hydra deals 1 damage to any target. {T}: Put a +1/+1 counter on Clockwork Hydra.

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

Whenever you cast a creature spell, draw a card.

Whenever a creature you control deals combat damage to a player, you may draw a card. {1}{U}, {T}: Creatures your opponents control attack this turn if able.

Target player draws X cards. Shuffle Blue Sun's Zenith into its owner's library.

Target player draws X cards.

Whenever a creature you control with a +1/+1 counter on it deals combat damage to a player, you may draw a card.

Enchant creature Whenever enchanted creature deals damage to an opponent, you may draw a card.

Whenever a creature deals combat damage to one of your opponents, its controller may draw a card.

Whenever a creature with power 3 or greater enters the battlefield under your control, draw a card.

Reveal the top X cards of your library. Put all creature cards revealed this way into your hand and the rest on the bottom of your library in any order.

Whenever another creature with power 3 or greater enters the battlefield under your control, you may 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.

Whenever a nontoken creature enters the battlefield under your control, if it doesn't have the same name as another creature you control or a creature card in your graveyard, draw a card.

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.

As Icon of Ancestry enters the battlefield, choose a creature type. Creatures you control of the chosen type get +1/+1. {3}, {T}: Look at the top three cards of your library. You may reveal a creature card of the chosen type from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Whenever a creature with power 4 or greater enters the battlefield under your control, draw a card. −1: Untap target permanent.

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.

At the beginning of your upkeep, scry 1. Whenever you cast a creature spell, you may pay {G}. If you do, draw a card.

Attacking creatures you control have deathtouch. Whenever a creature you control deals combat damage to a player, draw a card.

Flash (You may cast this spell any time you could cast an instant.) Enchant creature Whenever enchanted creature deals damage to an opponent, you may draw a card.

When Regal Force enters the battlefield, draw a card for each green creature you control.

Whenever you cast a spell with mana value 5 or greater, draw a card.

Bojuka Bog enters the battlefield tapped. When Bojuka Bog enters the battlefield, exile target player's graveyard. {T}: Add {B}.

({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.

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.

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

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}.

Drowned Catacomb enters the battlefield tapped unless you control an Island or a Swamp. {T}: Add {U} or {B}.

{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.

({T}: Add {G}.)

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}.

Hinterland Harbor enters the battlefield tapped unless you control a Forest or an Island. {T}: Add {G} or {U}.

({T}: Add {U}.)

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.

{T}: Add {C}. {2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

({T}: Add {B} or {G}.) As Overgrown Tomb enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

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.)

You have no maximum hand size. {T}: Add {C}.

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

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 {U} or {B}.) Sunken Hollow enters the battlefield tapped unless you control two or more basic lands.

({T}: Add {B}.)

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

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.

({T}: Add {U} or {B}.) As Watery Grave enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

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.

As Herald's Horn enters the battlefield, choose a creature type. Creature spells you cast of the chosen type cost {1} less to cast. At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

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.

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 Urza's Incubator enters the battlefield, choose a creature type. Creature spells of the chosen type cost {2} less to cast.

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

Return all nonland permanents with mana value X or less to their owners' hands.

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.

Polukranos enters the battlefield with six +1/+1 counters on it. It escapes with twelve +1/+1 counters on it instead. If damage would be dealt to Polukranos while it has a +1/+1 counter on it, prevent that damage and remove that many +1/+1 counters from it. {1}{B}{G}: Polukranos fights another target creature. Escape—{4}{B}{G}, Exile six other cards from your graveyard.

{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.

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.

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.

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.

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.) Search your library for a creature card with mana value X or less, put it onto the battlefield, then shuffle.

As Adaptive Automaton enters the battlefield, choose a creature type. Adaptive Automaton is the chosen type in addition to its other types. Other creatures you control of the chosen type get +1/+1.

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.

As Cloud Key enters the battlefield, choose artifact, creature, enchantment, instant, or sorcery. Spells you cast of the chosen type cost {1} less to cast.

Enchant player Whenever enchanted player is attacked, you draw a card. Each opponent attacking that player does the same.