{T}: Add one mana of any color in your commander's color identity.
{X}{X}{X}
Astral Cornucopia
Artifact
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.
{2}{G}
Beast Within
Instant
Destroy target permanent. Its controller creates a 3/3 green Beast creature token.
{X}{U}{U}{U}
Blue Sun's Zenith
Instant
Target player draws X cards. Shuffle Blue Sun's Zenith into its owner's library.
--
Bojuka Bog
Land
Bojuka Bog enters the battlefield tapped.
When Bojuka Bog enters the battlefield, exile target player's graveyard.
{T}: Add {B}.
{X}{G}
Capricopian
Creature - Goat Hydra
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.)
0 /
0
{5}
Clockwork Hydra
Artifact Creature - Hydra
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.
0 /
0
--
Command Tower
Land
{T}: Add one mana of any color in your commander's color identity.
{2}{B}{G}
Corpsejack Menace
Creature - Fungus
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.
4 /
4
{2}{G}
Cultivate
Sorcery
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.
{2}{G}
Elemental Bond
Enchantment
Whenever a creature with power 3 or greater enters the battlefield under your control, draw a card.
--
Exotic Orchard
Land
{T}: Add one mana of any color that a land an opponent controls could produce.
{X}{B}{B}
Exsanguinate
Sorcery
Each opponent loses X life. You gain life equal to the life lost this way.
{1}{G}
Farseek
Sorcery
Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.
{X}{G}
Feral Hydra
Creature - Hydra Beast
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.
0 /
0
--
Forest
Basic Land - Forest
({T}: Add {G}.)
{3}{G}{G}{G}
Gargos, Vicious Watcher
Legendary Creature - Hydra
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.
8 /
7
{2}{G}
Garruk's Uprising
Enchantment
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.
--
Golgari Guildgate
Land - Gate
Golgari Guildgate enters the battlefield tapped.
{T}: Add {B} or {G}.
{3}{G}{G}
Heroes' Bane
Creature - Hydra
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.
0 /
0
--
Hinterland Harbor
Land
Hinterland Harbor enters the battlefield tapped unless you control a Forest or an Island.
{T}: Add {G} or {U}.
{X}{G}{G}
Hooded Hydra
Creature - Snake Hydra
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.
0 /
0
{X}{G}
Hungering Hydra
Creature - Hydra
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.)
0 /
0
{2}{G}
Hydra's Growth
Enchantment - Aura
Enchant creature
When Hydra's Growth enters the battlefield, put a +1/+1 counter on enchanted creature.
At the beginning of your upkeep, double the number of +1/+1 counters on enchanted creature.
{X}{G}{U}
Hydroid Krasis
Creature - Jellyfish Hydra Beast
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.
0 /
0
{X}{U}
Ingenious Prodigy
Creature - Human Wizard
Skulk (This creature can't be blocked by creatures with greater power.)
Ingenious Prodigy enters the battlefield with X +1/+1 counters on it.
At the beginning of your upkeep, if Ingenious Prodigy has one or more +1/+1 counters on it, you may remove a +1/+1 counter from it. If you do, draw a card.
0 /
1
--
Island
Basic Land - Island
({T}: Add {U}.)
--
Lair of the Hydra
Land
If you control two or more other lands, Lair of the Hydra enters the battlefield tapped.
{T}: Add {G}.
{X}{G}: Until end of turn, Lair of the Hydra becomes an X/X green Hydra creature. It's still a land. X can't be 0.
{X}{G}
Mana Bloom
Enchantment
Mana Bloom enters the battlefield with X charge counters on it.
Remove a charge counter from Mana Bloom: Add one mana of any color. Activate only once each turn.
At the beginning of your upkeep, if Mana Bloom has no charge counters on it, return it to its owner's hand.
--
Mortuary Mire
Land
Mortuary Mire enters the battlefield tapped.
When Mortuary Mire enters the battlefield, you may put target creature card from your graveyard on top of your library.
{T}: Add {B}.
--
Opulent Palace
Land
Opulent Palace enters the battlefield tapped.
{T}: Add {B}, {G}, or {U}.
--
Path of Ancestry
Land
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.)
{1}{G}
Rampant Growth
Sorcery
Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
{X}{G}{U}
Repulsive Mutation
Instant
Put X +1/+1 counters on target creature you control. Then counter up to one target spell unless its controller pays mana equal to the greatest power among creatures you control.
{3}
Simic Cluestone
Artifact
{T}: Add {G} or {U}.
{G}{U}, {T}, Sacrifice Simic Cluestone: Draw a card.
--
Simic Guildgate
Land - Gate
Simic Guildgate enters the battlefield tapped.
{T}: Add {G} or {U}.
--
Simic Guildgate
Land - Gate
Simic Guildgate enters the battlefield tapped.
{T}: Add {G} or {U}.
{X}{B}
Slice from the Shadows
Instant
This spell can't be countered. (This includes by the ward ability.)
Target creature gets -X/-X until end of turn.
{1}
Sol Ring
Artifact
{T}: Add {C}{C}.
--
Swamp
Basic Land - Swamp
({T}: Add {B}.)
--
Temple of the False God
Land
{T}: Add {C}{C}. Activate only if you control five or more lands.
{X}{G}{U}
The Goose Mother
Legendary Creature - Bird Hydra
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.
2 /
2
{2}
Thought Vessel
Artifact
You have no maximum hand size.
{T}: Add {C}.
{X}{G}{G}
Vastwood Hydra
Creature - Hydra
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.
0 /
0
{3}
Zagoth Crystal
Artifact
{T}: Add {B}, {G}, or {U}.
Cycling {2} ({2}, Discard this card: Draw a card.)
{1}{B}{G}{U}
Zaxara, the Exemplary
Legendary Creature - Nightmare Hydra
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.
2 /
3
{2}{G}
Cultivate
Sorcery
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.
{2}{G}
Elemental Bond
Enchantment
Whenever a creature with power 3 or greater enters the battlefield under your control, draw a card.
{1}{G}
Farseek
Sorcery
Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.
{2}{G}
Garruk's Uprising
Enchantment
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.
{1}{G}
Rampant Growth
Sorcery
Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
--
Temple of the False God
Land
{T}: Add {C}{C}. Activate only if you control five or more lands.