Windborn Muse

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

Proxy 

Teferi's Protection

Until your next turn, your life total can't change and you gain protection from everything. All permanents you control phase out. (While they're phased out, they're treated as though they don't exist. They phase in before you untap during your untap step.)
Exile Teferi's Protection.

Path of Ancestry

Path of Ancestry enters 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.)

Myriad Landscape

Myriad Landscape enters 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.

Clarion Spirit

Whenever you cast your second spell each turn, create a 1/1 white Spirit creature token with flying.

Command Tower

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

Bojuka Bog

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

Coat of Arms

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.)

Plains

Drogskol Reinforcements

Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)
Other Spirits you control have melee.
Prevent all noncombat damage that would be dealt to Spirits you control.

Moonshaker Cavalry

Flying
When Moonshaker Cavalry enters, creatures you control gain flying and get +X/+X until end of turn, where X is the number of creatures you control.

Tainted Field

{T}: Add {C}.
{T}: Add {W} or {B}. Activate only if you control a Swamp.

Temple of the False God

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

Grey Host Reinforcements

Flying, ward {3}
When Grey Host Reinforcements enters, exile target player's graveyard. Put a number of +1/+1 counters on Grey Host Reinforcements equal to the number of creature cards exiled this way.

Andúril, Flame of the West

Equipped creature gets +3/+1.
Whenever equipped creature attacks, create two tapped 1/1 white Spirit creature tokens with flying. If that creature is legendary, instead create two of those tokens that are tapped and attacking.
Equip {2}

Shadow Summoning

Create two tapped 1/1 white Spirit creature tokens with flying.

Godless Shrine

({T}: Add {W} or {B}.)
As Godless Shrine enters, you may pay 2 life. If you don't, it enters tapped.

Eerie Interlude

Exile any number of target creatures you control. Return those cards to the battlefield under their owner's control at the beginning of the next end step.

Cauldron Haze

Choose any number of target creatures. Each of those creatures gains persist until end of turn. (When it dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Staff of the Storyteller

When Staff of the Storyteller enters, create a 1/1 white Spirit creature token with flying.
Whenever you create one or more creature tokens, put a story counter on Staff of the Storyteller.
{W}, {T}, Remove a story counter from Staff of the Storyteller: Draw a card.

Everything Comes to Dust

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.)
Exile all creatures except those that share a creature type with a creature that convoked this spell, all artifacts, and all enchantments.

Skullclamp

Equipped creature gets +1/-1.
Whenever equipped creature dies, draw two cards.
Equip {1}

Drumbellower

Flying
Untap all creatures you control during each other player's untap step.

Shineshadow Snarl

As Shineshadow Snarl enters, you may reveal a Plains or Swamp card from your hand. If you don't, Shineshadow Snarl enters tapped.
{T}: Add {W} or {B}.

Sol Ring

Thought Vessel

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

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Katilda's Rising Dawn

Enchant creature
Enchanted creature has flying, lifelink, and protection from Vampires, and it gets +X/+X, where X is the number of permanents you control that are Spirits and/or enchantments.
If Katilda's Rising Dawn would be put into a graveyard from anywhere, exile it instead.

Katilda, Dawnhart Martyr

Flying, lifelink, protection from Vampires
Katilda, Dawnhart Martyr's power and toughness are each equal to the number of permanents you control that are Spirits and/or enchantments.
Disturb {3}{W}{W} (You may cast this card from your graveyard transformed for its disturb cost.)

Katilda, Dawnhart Martyr // Katilda's Rising Dawn

Horobi, Death's Wail

Flying
Whenever a creature becomes the target of a spell or ability, destroy that creature.

Inspiring Leader

Commander creatures you own have "Creature tokens you control get +2/+2."

Drogskol Cavalry

Flying
Whenever another Spirit you control enters, you gain 2 life.
{3}{W}: Create a 1/1 white Spirit creature token with flying.

Vault of Champions

Vault of Champions enters tapped unless you have two or more opponents.
{T}: Add {W} or {B}.

Orzhov Signet

Cabal Coffers

{2}, {T}: Add {B} for each Swamp you control.

Lingering Souls

Create two 1/1 white Spirit creature tokens with flying.
Flashback {1}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Haunted Library

Whenever a creature an opponent controls dies, you may pay {1}. If you do, create a 1/1 white Spirit creature token with flying.

King of the Oathbreakers

Flying
Whenever King of the Oathbreakers or another Spirit you control becomes the target of a spell, it phases out. (Treat it and anything attached to it as though they don't exist until your next turn.)
Whenever King of the Oathbreakers or another Spirit you control phases in, create a tapped 1/1 white Spirit creature token with flying.

Guardian of Faith

Flash
Vigilance
When Guardian of Faith enters, any number of other target creatures you control phase out. (Treat them and anything attached to them as though they don't exist until their controller's next turn.)

V.A.T.S.

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Choose any number of target creatures with equal toughness. Destroy the chosen creatures.

He Who Hungers

Flying
{1}, Sacrifice a Spirit: Target opponent reveals their hand. You choose a card from it. That player discards that card. Activate only as a sorcery.
Soulshift 4 (When this creature dies, you may return target Spirit card with mana value 4 or less from your graveyard to your hand.)

Isolated Chapel

Isolated Chapel enters tapped unless you control a Plains or a Swamp.
{T}: Add {W} or {B}.

Temple of Civilization

(Transforms from Ojer Taq, Deepest Foundation.)
{T}: Add {W}.
{2}{W}, {T}: Transform Temple of Civilization. Activate only if you attacked with three or more creatures this turn and only as a sorcery.

Ojer Taq, Deepest Foundation

Vigilance
If one or more creature tokens would be created under your control, three times that many of those tokens are created instead.
When Ojer Taq dies, return it to the battlefield tapped and transformed under its owner's control.

Ojer Taq, Deepest Foundation // Temple of Civilization

Divinity of Pride

Flying, lifelink
Divinity of Pride gets +4/+4 as long as you have 25 or more life.

Shattered Sanctum

Shattered Sanctum enters tapped unless you control two or more other lands.
{T}: Add {W} or {B}.

Oyobi, Who Split the Heavens

Flying
Whenever you cast a Spirit or Arcane spell, create a 3/3 white Spirit creature token with flying.

Fetid Heath

{T}: Add {C}.
{W/B}, {T}: Add {W}{W}, {W}{B}, or {B}{B}.

Myojin of Blooming Dawn

Myojin of Blooming Dawn enters with an indestructible counter on it if you cast it from your hand.
Remove an indestructible counter from Myojin of Blooming Dawn: Create a 1/1 colorless Spirit creature token for each permanent you control.

Swamp

Cathars' Crusade

Whenever a creature you control enters, put a +1/+1 counter on each creature you control.

Semester's End

Exile any number of target creatures and/or planeswalkers you control. At the beginning of the next end step, return each of them to the battlefield under its owner's control. Each of them enters with an additional +1/+1 counter on it if it's a creature and an additional loyalty counter on it if it's a planeswalker.

Minas Tirith

Minas Tirith enters tapped unless you control a legendary creature.
{T}: Add {W}.
{1}{W}, {T}: Draw a card. Activate only if you attacked with two or more creatures this turn.

Remorseful Cleric

Flying
Sacrifice Remorseful Cleric: Exile target player's graveyard.

Despark

Exile target permanent with mana value 4 or greater.

Galadriel's Dismissal

Kicker {2}{W} (You may pay an additional {2}{W} as you cast this spell.)
Target creature phases out. If this spell was kicked, each creature target player controls phases out instead. (Treat phased-out creatures and anything attached to them as though they don't exist until their controller's next turn.)

Hour of Reckoning

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.)
Destroy all nontoken creatures.

Nikko-Onna

When Nikko-Onna enters, destroy target enchantment.
Whenever you cast a Spirit or Arcane spell, you may return Nikko-Onna to its owner's hand.

Twilight Drover

Whenever a creature token leaves the battlefield, put a +1/+1 counter on Twilight Drover.
{2}{W}, Remove a +1/+1 counter from Twilight Drover: Create two 1/1 white Spirit creature tokens with flying.

Anointed Procession

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

Flowering of the White Tree

Legendary creatures you control get +2/+1 and have ward {1}.
Nonlegendary creatures you control get +1/+1.

Release to Memory

Exile target opponent's graveyard. For each creature card exiled this way, create a 1/1 colorless Spirit creature token.

Kami of False Hope

Sacrifice Kami of False Hope: Prevent all combat damage that would be dealt this turn.

In Garruk's Wake

Destroy all creatures you don't control and all planeswalkers you don't control.

Devouring Greed

As an additional cost to cast this spell, you may sacrifice any number of Spirits.
Target player loses 2 life plus 2 life for each Spirit sacrificed this way. You gain that much life.

Swords to Plowshares

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

Scapegoat

As an additional cost to cast this spell, sacrifice a creature.
Return any number of target creatures you control to their owner's hand.

Crypt Ghast

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Whenever you tap a Swamp for mana, add an additional {B}.

Thalisse, Reverent Medium

At the beginning of each end step, create X 1/1 white Spirit creature tokens with flying, where X is the number of tokens you created this turn.

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

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.

Touch of Darkness

One or more target creatures become black until end of turn.

Anguished Unmaking

Exile target nonland permanent. You lose 3 life.

Selfless Spirit

Flying
Sacrifice Selfless Spirit: Creatures you control gain indestructible until end of turn.

Vault of the Archangel

{T}: Add {C}.
{2}{W}{B}, {T}: Creatures you control gain deathtouch and lifelink until end of turn.

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Arcane Signet

Heaven's Gate

One or more target creatures become white until end of turn.

Grimclimb Pathway

Brightclimb Pathway

Brightclimb Pathway // Grimclimb Pathway

Intangible Virtue

Creature tokens you control get +1/+1 and have vigilance.

Clever Concealment

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.)
Any number of target nonland permanents you control phase out. (Treat them and anything attached to them as though they don't exist until your next turn.)

The Broken Sky

Creature tokens you control get +1/+0 and have lifelink.
At the beginning of your end step, create a 1/1 white and black Spirit creature token with flying.

Invasion of Tolvada

(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)
When Invasion of Tolvada enters, return target nonbattle permanent card from your graveyard to the battlefield.

Invasion of Tolvada // The Broken Sky

Mondrak, Glory Dominus

If one or more tokens would be created under your control, twice that many of those tokens are created instead.
{1}{W/P}{W/P}, Sacrifice two other artifacts and/or creatures: Put an indestructible counter on Mondrak, Glory Dominus. ({W/P} can be paid with either {W} or 2 life.)

Roaming Throne

Ward {2}
As Roaming Throne enters, choose a creature type.
Roaming Throne is the chosen type in addition to its other types.
If a triggered ability of another creature you control of the chosen type triggers, it triggers an additional time.

Mirror Entity

Changeling (This card is every creature type.)
{X}: Until end of turn, creatures you control have base power and toughness X/X and gain all creature types.

Pollen Remedy

Kicker—Sacrifice a land. (You may sacrifice a land in addition to any other costs as you cast this spell.)
Prevent the next 3 damage that would be dealt this turn to any number of targets, divided as you choose. If this spell was kicked, prevent the next 6 damage this way instead.

Reliquary Tower

Remedy

Prevent the next 5 damage that would be dealt this turn to any number of targets, divided as you choose.