Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Graveshifter

Changeling (This card is every creature type.)
When Graveshifter enters the battlefield, you may return target creature card from your graveyard to your hand.

Island

Hallowed Respite

Exile target nonlegendary creature, then return it to the battlefield under its owner's control. If it entered under your control, put a +1/+1 counter on it. Otherwise, tap it.
Flashback {1}{W}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

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.

Swiftwater Cliffs

Swiftwater Cliffs enters the battlefield tapped.
When Swiftwater Cliffs enters the battlefield, you gain 1 life.
{T}: Add {U} or {R}.

Alrund's Epiphany

Create two 1/1 blue Bird creature tokens with flying. Take an extra turn after this one. Exile Alrund's Epiphany.
Foretell {4}{U}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Plains

Etherium Spinner

Whenever you cast a spell with mana value 4 or greater, create a 1/1 colorless Thopter artifact creature token with flying.

Krenko, Mob Boss

{T}: Create X 1/1 red Goblin creature tokens, where X is the number of Goblins you control.

Irregular Cohort

Changeling (This card is every creature type.)
When Irregular Cohort enters the battlefield, create a 2/2 colorless Shapeshifter creature token with changeling.

Replicating Ring

{T}: Add one mana of any color.
At the beginning of your upkeep, put a night counter on Replicating Ring. Then if it has eight or more night counters on it, remove all of them and create eight colorless snow artifact tokens named Replicated Ring with "{T}: Add one mana of any color."

Forest

Scuttlemutt

{T}: Add one mana of any color.
{T}: Target creature becomes the color or colors of your choice until end of turn.

Astral Drift

Whenever you cycle Astral Drift or cycle another card while Astral Drift is on the battlefield, you may exile target creature. If you do, return that card to the battlefield under its owner's control at the beginning of the next end step.
Cycling {2}{W} ({2}{W}, Discard this card: Draw a card.)

War's Toll

Whenever an opponent taps a land for mana, tap all lands that player controls.
If a creature an opponent controls attacks, all creatures that opponent controls attack if able.

Simic Growth Chamber

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}.

Riku of Two Reflections

Whenever you cast an instant or sorcery spell, you may pay {U}{R}. If you do, copy that spell. You may choose new targets for the copy.
Whenever another nontoken creature enters the battlefield under your control, you may pay {G}{U}. If you do, create a token that's a copy of that creature.

Gateway Plaza

Gateway Plaza enters the battlefield tapped.
When Gateway Plaza enters the battlefield, sacrifice it unless you pay {1}.
{T}: Add one mana of any color.

Mirrorworks

Whenever another nontoken artifact enters the battlefield under your control, you may pay {2}. If you do, create a token that's a copy of that artifact.

Anger

Haste
As long as Anger is in your graveyard and you control a Mountain, creatures you control have haste.

Boros Garrison

Boros Garrison enters the battlefield tapped.
When Boros Garrison enters the battlefield, return a land you control to its owner's hand.
{T}: Add {R}{W}.

Chromatic Orrery

You may spend mana as though it were mana of any color.
{T}: Add {C}{C}{C}{C}{C}.
{5}, {T}: Draw a card for each color among permanents you control.

Firemind Vessel

Firemind Vessel enters the battlefield tapped.
{T}: Add two mana of different colors.

Cunning Evasion

Whenever a creature you control becomes blocked, you may return it to its owner's hand.

Lithoform Engine

{2}, {T}: Copy target activated or triggered ability you control. You may choose new targets for the copy.
{3}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.
{4}, {T}: Copy target permanent spell you control. (The copy becomes a token.)

Jungle Basin

Jungle Basin enters the battlefield tapped.
When Jungle Basin enters the battlefield, sacrifice it unless you return an untapped Forest you control to its owner's hand.
{T}: Add {C}{G}.

Jungle Shrine

Jungle Shrine enters the battlefield tapped.
{T}: Add {R}, {G}, or {W}.

Bloodline Pretender

Changeling (This card is every creature type.)
As Bloodline Pretender enters the battlefield, choose a creature type.
Whenever another creature of the chosen type enters the battlefield under your control, put a +1/+1 counter on Bloodline Pretender.

Scoured Barrens

Scoured Barrens enters the battlefield tapped.
When Scoured Barrens enters the battlefield, you gain 1 life.
{T}: Add {W} or {B}.

Frontier Bivouac

Frontier Bivouac enters the battlefield tapped.
{T}: Add {G}, {U}, or {R}.

Reaper King

({2/W} can be paid with any two mana or with {W}. This card's mana value is 10.)
Other Scarecrow creatures you control get +1/+1.
Whenever another Scarecrow enters the battlefield under your control, destroy target permanent.

Gruul Turf

Gruul Turf enters the battlefield tapped.
When Gruul Turf enters the battlefield, return a land you control to its owner's hand.
{T}: Add {R}{G}.

Teleportation Circle

At the beginning of your end step, exile up to one target artifact or creature you control, then return that card to the battlefield under its owner's control.

One-Eyed Scarecrow

Defender
Creatures with flying your opponents control get -1/-0.

Thassa, Deep-Dwelling

Indestructible
As long as your devotion to blue is less than five, Thassa isn't a creature.
At the beginning of your end step, exile up to one other target creature you control, then return that card to the battlefield under your control.
{3}{U}: Tap another target creature.

Bloodfell Caves

Bloodfell Caves enters the battlefield tapped.
When Bloodfell Caves enters the battlefield, you gain 1 life.
{T}: Add {B} or {R}.

Biblioplex Assistant

Flying
When Biblioplex Assistant enters the battlefield, put up to one target instant or sorcery card from your graveyard on top of your library.

Into the Wilds

At the beginning of your upkeep, look at the top card of your library. If it's a land card, you may put it onto the battlefield.

Realmwalker

Changeling (This card is every creature type.)
As Realmwalker enters the battlefield, choose a creature type.
You may look at the top card of your library any time.
You may cast creature spells of the chosen type from the top of your library.

Shimmering Grotto

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Crumbling Necropolis

Crumbling Necropolis enters the battlefield tapped.
{T}: Add {U}, {B}, or {R}.

Unknown Shores

Reflections of Littjara

As Reflections of Littjara enters the battlefield, choose a creature type.
Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

Karoo

Karoo enters the battlefield tapped.
When Karoo enters the battlefield, sacrifice it unless you return an untapped Plains you control to its owner's hand.
{T}: Add {C}{W}.

Dissipate

Counter target spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Vessel of Endless Rest

When Vessel of Endless Rest enters the battlefield, put target card from a graveyard on the bottom of its owner's library.
{T}: Add one mana of any color.

Flicker of Fate

Exile target creature or enchantment, then return it to the battlefield under its owner's control.

Sunken Hope

At the beginning of each player's upkeep, that player returns a creature they control to its owner's hand.

Mountain

Rush of Knowledge

Draw cards equal to the highest mana value among permanents you control.

Scaretiller

Whenever Scaretiller becomes tapped, choose one —
• You may put a land card from your hand onto the battlefield tapped.
• Return target land card from your graveyard to the battlefield tapped.

Heroic Intervention

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

Power Depot

Power Depot enters the battlefield tapped.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast artifact spells or activate abilities of artifacts.
Modular 1

Exotic Orchard

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

Morophon, the Boundless

Changeling (This card is every creature type.)
As Morophon, the Boundless enters the battlefield, choose a creature type.
Spells of the chosen type you cast cost {W}{U}{B}{R}{G} less to cast. This effect reduces only the amount of colored mana you pay.
Other creatures you control of the chosen type get +1/+1.

Displace

Exile up to two target creatures you control, then return those cards to the battlefield under their owner's control.

Solemn Simulacrum

When Solemn Simulacrum enters the battlefield, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Molten Echoes

As Molten Echoes enters the battlefield, choose a creature type.
Whenever a nontoken creature of the chosen type enters the battlefield under your control, create a token that's a copy of that creature. That token gains haste. Exile it at the beginning of the next end step.

Confounding Conundrum

When Confounding Conundrum enters the battlefield, draw a card.
Whenever a land enters the battlefield under an opponent's control, if that player had another land enter the battlefield under their control this turn, they return a land they control to its owner's hand.

Scarecrone

{1}, Sacrifice a Scarecrow: Draw a card.
{4}, {T}: Return target artifact creature card from your graveyard to the battlefield.

Command Tower

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

Opulent Palace

Opulent Palace enters the battlefield tapped.
{T}: Add {B}, {G}, or {U}.

Panharmonicon

If an artifact or creature entering the battlefield causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Valor

First strike
As long as Valor is in your graveyard and you control a Plains, creatures you control have first strike.

Muldrotha, the Gravetide

During each of your turns, you may play a land and cast a permanent spell of each permanent type from your graveyard. (If a card has multiple permanent types, choose one as you play it.)

Armillary Sphere

{2}, {T}, Sacrifice Armillary Sphere: Search your library for up to two basic land cards, reveal them, put them into your hand, then shuffle.

Twinflame

Strive — This spell costs {2}{R} more to cast for each target beyond the first.
Choose any number of target creatures you control. For each of them, create a token that's a copy of that creature, except it has haste. Exile those tokens at the beginning of the next end step.

Maskwood Nexus

Creatures you control are every creature type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.
{3}, {T}: Create a 2/2 blue Shapeshifter creature token with changeling. (It is every creature type.)

Rite of Replication

Kicker {5} (You may pay an additional {5} as you cast this spell.)
Create a token that's a copy of target creature. If this spell was kicked, create five of those tokens instead.

Tranquil Cove

Tranquil Cove enters the battlefield tapped.
When Tranquil Cove enters the battlefield, you gain 1 life.
{T}: Add {W} or {U}.

Swamp

Cloudshift

Exile target creature you control, then return that card to the battlefield under your control.

Negate

Momentary Blink

Exile target creature you control, then return it to the battlefield under its owner's control.
Flashback {3}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

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

Trostani, Selesnya's Voice

Whenever another creature enters the battlefield under your control, you gain life equal to that creature's toughness.
{1}{G}{W}, {T}: Populate. (Create a token that's a copy of a creature token you control.)

Double Vision

Whenever you cast your first instant or sorcery spell each turn, copy that spell. You may choose new targets for the copy.

Soulherder

Whenever a creature is exiled from the battlefield, put a +1/+1 counter on Soulherder.
At the beginning of your end step, you may exile another target creature you control, then return that card to the battlefield under its owner's control.

Sol Ring

Annul

Counter target artifact or enchantment spell.

Blacksmith's Skill

Target permanent gains hexproof and indestructible until end of turn. If it's an artifact creature, it gets +2/+2 until end of turn.

Acrobatic Maneuver

Exile target creature you control, then return that card to the battlefield under its owner's control.
Draw a card.

Wild-Field Scarecrow

Defender
{2}, Sacrifice Wild-Field Scarecrow: Search your library for up to two basic land cards, reveal them, put them into your hand, then shuffle.

Hero of Bretagard

Whenever one or more cards are put into exile from your hand or a spell or ability you control exiles one or more permanents from the battlefield, put that many +1/+1 counters on Hero of Bretagard.
As long as Hero of Bretagard has five or more counters on it, it has flying and is an Angel in addition to its other types.
As long as Hero of Bretagard has ten or more counters on it, it has indestructible and is a God in addition to its other types.

Blossoming Sands

Blossoming Sands enters the battlefield tapped.
When Blossoming Sands enters the battlefield, you gain 1 life.
{T}: Add {G} or {W}.

Hall of Heliod's Generosity

{T}: Add {C}.
{1}{W}, {T}: Put target enchantment card from your graveyard on top of your library.