Primeval Spawn

If Primeval Spawn would enter the battlefield and it wasn't cast or no mana was spent to cast it, exile it instead.
Vigilance, trample, lifelink
When Primeval Spawn leaves the battlefield, exile the top ten cards of your library. You may cast any number of spells with total mana value 10 or less from among them without paying their mana costs.

Tangleweave Armor

Living weapon (When this Equipment enters the battlefield, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +X/+X, where X is the greatest mana value among your commanders.
Equip {4}

Apocalypse Hydra

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.

Rhythm of the Wild

Creature spells you control can't be countered.
Nontoken creatures you control have riot. (They enter the battlefield with your choice of a +1/+1 counter or haste.)

Tempt with Discovery

Tempting offer — Search your library for a land card and put it onto the battlefield. Each opponent may search their library for a land card and put it onto the battlefield. For each opponent who searches a library this way, search your library for a land card and put it onto the battlefield. Then each player who searched a library this way shuffles.

Feral Hydra

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.

Briar Hydra

Trample
Domain — Whenever Briar Hydra deals combat damage to a player, put X +1/+1 counters on target creature you control, where X is the number of basic land types among lands you control.

Hydroid Krasis

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.

Prevent all combat damage that would be dealt this turn.

Maelstrom Nexus

The first spell you cast each turn has cascade. (When you cast your first spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom of your library in a random order.)

Command Tower

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

Zaxara, the Exemplary

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.

Sol Ring

Unbound Flourishing

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.

Cascading Cataracts

Indestructible
{T}: Add {C}.
{5}, {T}: Add five mana in any combination of colors.

Eerie Ultimatum

Return any number of permanent cards with different names from your graveyard to the battlefield.

Clockwork 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.

Temur Ascendancy

Creatures you control have haste.
Whenever a creature with power 4 or greater enters the battlefield under your control, you may draw a card.

Ruinous Ultimatum

Destroy all nonland permanents your opponents control.

Fellwar Stone

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

The Great Henge

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.

Bloom Tender

{T}: For each color among permanents you control, add one mana of that color.

Benevolent Hydra

Benevolent Hydra enters the battlefield with X +1/+1 counters on it.
If one or more +1/+1 counters would be put on another creature you control, that many plus one +1/+1 counters are put on it instead.
{T}, Remove a +1/+1 counter from Benevolent Hydra: Put a +1/+1 counter on another target creature you control.

Explosive Vegetation

Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Hydra's Growth

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.

Door to Nothingness

Door to Nothingness enters the battlefield tapped.
{W}{W}{U}{U}{B}{B}{R}{R}{G}{G}, {T}, Sacrifice Door to Nothingness: Target player loses the game.

Growth Spiral

Draw a card. You may put a land card from your hand onto the battlefield.

Forest

Birds of Paradise

Cultivate

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.

Heroic Intervention

Permanents you control gain hexproof and indestructible until end of turn.

Arcane Signet

The Prismatic Bridge

At the beginning of your upkeep, reveal cards from the top of your library until you reveal a creature or planeswalker card. Put that card onto the battlefield and the rest on the bottom of your library in a random order.

Esika, God of the Tree

Vigilance
{T}: Add one mana of any color.
Other legendary creatures you control have vigilance and "{T}: Add one mana of any color."

Esika, God of the Tree // The Prismatic Bridge

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Kodama's Reach

Mirari's Wake

Creatures you control get +1/+1.
Whenever you tap a land for mana, add one mana of any type that land produced.

Ramos, Dragon Engine

Flying
Whenever you cast a spell, put a +1/+1 counter on Ramos, Dragon Engine for each of that spell's colors.
Remove five +1/+1 counters from Ramos: Add {W}{W}{U}{U}{B}{B}{R}{R}{G}{G}. Activate only once each turn.

O-Kagachi, Vengeful Kami

Flying, trample
Whenever O-Kagachi, Vengeful Kami deals combat damage to a player, if that player attacked you during their last turn, exile target nonland permanent that player controls.

Plains

Maelstrom Archangel

Flying
Whenever Maelstrom Archangel deals combat damage to a player, you may cast a spell from your hand without paying its mana cost.

Terramorphic Expanse

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

Progenitus

Protection from everything
If Progenitus would be put into a graveyard from anywhere, reveal Progenitus and shuffle it into its owner's library instead.

Evolving Wilds

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

Dryad of the Ilysian Grove

You may play an additional land on each of your turns.
Lands you control are every basic land type in addition to their other types.

Up the Beanstalk

When Up the Beanstalk enters the battlefield and whenever you cast a spell with mana value 5 or greater, draw a card.

Unite the Coalition

Choose five. You may choose the same mode more than once.
• Target permanent phases out.
• Target player draws a card.
• Exile target player's graveyard.
• Unite the Coalition deals 2 damage to any target.
• Destroy target artifact or enchantment.

Negate

Counterspell

Ironscale Hydra

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

Swamp

Wrenn and Realmbreaker

Lands you control have "{T}: Add one mana of any color."
+1: Up to one target land you control becomes a 3/3 Elemental creature with vigilance, hexproof, and haste until your next turn. It's still a land.
−2: Mill three cards. You may put a permanent card from among the milled cards into your hand.
−7: You get an emblem with "You may play lands and cast permanent spells from your graveyard."

Circuitous Route

Search your library for up to two basic land cards and/or Gate cards, put them onto the battlefield tapped, then shuffle.

Rampant Growth

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

Iridian Maelstrom

Destroy each creature that isn't all colors.

Rafiq of the Many

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
Whenever a creature you control attacks alone, it gains double strike until end of turn.

Hungering 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.)

Garruk's Uprising

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.

Last Stand

Target opponent loses 2 life for each Swamp you control. Last Stand deals damage to target creature equal to the number of Mountains you control. Create a 1/1 green Saproling creature token for each Forest you control. You gain 2 life for each Plains you control. Draw a card for each Island you control, then discard that many cards.

Ghostly Prison

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

Mountain

Island

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Sphinx of the Guildpact

Sphinx of the Guildpact is all colors.
Flying
Hexproof from monocolored (This creature can't be the target of monocolored spells or abilities your opponents control.)

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Chromanticore

Bestow {2}{W}{U}{B}{R}{G} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Flying, first strike, vigilance, trample, lifelink
Enchanted creature gets +4/+4 and has flying, first strike, vigilance, trample, and lifelink.

Fist of Suns

You may pay {W}{U}{B}{R}{G} rather than pay the mana cost for spells you cast.

Rising of the Day

Creatures you control have haste.
Legendary creatures you control get +1/+0.

Teyo, Geometric Tactician

When Teyo, Geometric Tactician enters the battlefield, create a 0/4 white Wall creature token with defender and flying.
+1: You and target opponent each draw a card.
−2: Choose left or right. Until your next turn, each player may attack only the nearest opponent in the last chosen direction and planeswalkers controlled by that opponent.