Kira, Great Glass-Spinner

Flying
Creatures you control have "Whenever this creature becomes the target of a spell or ability for the first time each turn, counter that spell or ability."

Command Tower

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

Donal, Herald of Wings

Whenever you cast a nonlegendary creature spell with flying, you may copy it, except the copy is a 1/1 Spirit in addition to its other types. Do this only once each turn. (The copy becomes a token.)

Prairie Stream

({T}: Add {W} or {U}.)
Prairie Stream enters tapped unless you control two or more basic lands.

Kindred Discovery

As Kindred Discovery enters, choose a creature type.
Whenever a creature you control of the chosen type enters or attacks, draw a card.

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.

Nanogene Conversion

Choose target creature you control. Each other creature becomes a copy of that creature until end of turn, except it isn't legendary.

Kirtar's Wrath

Destroy all creatures. They can't be regenerated.
Threshold — If seven or more cards are in your graveyard, instead destroy all creatures, then create two 1/1 white Spirit creature tokens with flying. Creatures destroyed this way can't be regenerated.

Spell Queller

Flash
Flying
When Spell Queller enters, exile target spell with mana value 4 or less.
When Spell Queller leaves the battlefield, the exiled card's owner may cast that card without paying its mana cost.

Skullclamp

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

Glacial Fortress

Glacial Fortress enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Spectral Arcanist

Flying
When Spectral Arcanist enters, you may cast an instant or sorcery spell with mana value less than or equal to the number of Spirits you control from a graveyard without paying its mana cost. If that spell would be put into a graveyard, exile it instead.

Patrician Geist

Flying
Other Spirits you control get +1/+1.
Spells you cast from your graveyard cost {1} less to cast.

Priest of the Blessed Graf

At the beginning of your end step, create X 1/1 white Spirit creature tokens with flying, where X is the number of opponents who control more lands than you.

Ghastly Mimicry

Enchant creature
At the beginning of your upkeep, create a token that's a copy of enchanted creature, except it's a Spirit in addition to its other types.
If Ghastly Mimicry would be put into a graveyard from anywhere, exile it instead.

Mirrorhall Mimic

You may have Mirrorhall Mimic enter as a copy of any creature on the battlefield, except it's a Spirit in addition to its other types.
Disturb {3}{U}{U} (You may cast this card from your graveyard transformed for its disturb cost.)

Mirrorhall Mimic // Ghastly Mimicry

Exotic Orchard

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

Spectral Sailor

Flash (You may cast this spell any time you could cast an instant.)
Flying
{3}{U}: Draw a card.

Reconnaissance Mission

Whenever a creature you control deals combat damage to a player, you may draw a card.
Cycling {2} ({2}, Discard this card: Draw a card.)

Release to Memory

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

Bygone Bishop

Flying
Whenever you cast a creature spell with mana value 3 or less, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Rattlechains

Flash
Flying
When Rattlechains enters, target Spirit gains hexproof until end of turn.
You may cast Spirit spells as though they had flash.

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.

Ethereal Investigator

Flying
When Ethereal Investigator enters, investigate X times, where X is the number of opponents you have. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Whenever you draw your second card each turn, create a 1/1 white Spirit creature token with flying.

Supreme Phantom

Flying
Other Spirits you control get +1/+1.

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

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.

Kiri-Onna

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

Windborn Muse

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

Drogskol Captain

Flying
Other Spirit creatures you control get +1/+1 and have hexproof. (They can't be the targets of spells or abilities your opponents control.)

Empyrean Eagle

Flying
Other creatures you control with flying get +1/+1.

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.

Titan of Littjara

As Titan of Littjara enters, choose a creature type.
Titan of Littjara is the chosen type in addition to its other types.
Whenever Titan of Littjara enters or attacks, you may draw a card for each other creature you control that shares a creature type with it. If you do, discard a card.

Sun Titan

Vigilance
Whenever Sun Titan enters or attacks, you may return target permanent card with mana value 3 or less from your graveyard to the battlefield.

March of Souls

Destroy all creatures. They can't be regenerated. For each creature destroyed this way, its controller creates a 1/1 white Spirit creature token with flying.

Hallowed Fountain

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

Sire of the Storm

Flying
Whenever you cast a Spirit or Arcane spell, you may draw a card.

Hanged Executioner

Flying
When Hanged Executioner enters, create a 1/1 white Spirit creature token with flying.
{3}{W}, Exile Hanged Executioner: Exile target creature.

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.

Sea of Clouds

Sea of Clouds enters tapped unless you have two or more opponents.
{T}: Add {W} or {U}.

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.

Mausoleum Wanderer

Flying
Whenever another Spirit you control enters, Mausoleum Wanderer gets +1/+1 until end of turn.
Sacrifice Mausoleum Wanderer: Counter target instant or sorcery spell unless its controller pays {X}, where X is Mausoleum Wanderer's power.

Bident of Thassa

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.

Storm of Souls

Return all creature cards from your graveyard to the battlefield. Each of them is a 1/1 Spirit with flying in addition to its other types. Exile Storm of Souls.

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.

Raise the Palisade

Choose a creature type. Return all creatures that aren't of the chosen type to their owners' hands.

Winged Words

This spell costs {1} less to cast if you control a creature with flying.
Draw two cards.

Cemetery Illuminator

Flying
Whenever Cemetery Illuminator enters or attacks, exile a card from a graveyard.
You may look at the top card of your library any time.
Once each turn, you may cast a spell from the top of your library if it shares a card type with a card exiled with Cemetery Illuminator.

Topplegeist

Flying
When Topplegeist enters, tap target creature an opponent controls.
Delirium — At the beginning of each opponent's upkeep, if there are four or more card types among cards in your graveyard, tap target creature that player controls.

Mystic Gate

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

Hollowhenge Spirit

Flash (You may cast this spell any time you could cast an instant.)
Flying
When Hollowhenge Spirit enters, remove target attacking or blocking creature from combat.

Unsettled Mariner

Changeling (This card is every creature type.)
Whenever you or a permanent you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {1}.

Kabira Plateau

Kabira Plateau enters tapped.
{T}: Add {W}.

Kabira Takedown

Kabira Takedown deals damage equal to the number of creatures you control to target creature or planeswalker.

Kabira Takedown // Kabira Plateau

Breath of the Sleepless

You may cast Spirit spells as though they had flash.
Whenever you cast a creature spell during an opponent's turn, tap up to one target creature.

Oyobi, Who Split the Heavens

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

Plains

Island

Remorseful Cleric

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

Skyclave Apparition

When Skyclave Apparition enters, exile up to one target nonland, nontoken permanent you don't control with mana value 4 or less.
When Skyclave Apparition leaves the battlefield, the exiled card's owner creates an X/X blue Illusion creature token, where X is the mana value of the exiled card.

Selfless Spirit

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

Spectral Adversary

Flash
Flying
When Spectral Adversary enters, you may pay {1}{U} any number of times. When you pay this cost one or more times, put that many +1/+1 counters on Spectral Adversary, then up to that many other target artifacts, creatures, and/or enchantments phase out.

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.)

Horn of the Mark

Whenever two or more creatures you control attack a player, look at the top five cards of your library. You may reveal a creature card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Millicent, Restless Revenant

This spell costs {1} less to cast for each Spirit you control.
Flying
Whenever Millicent, Restless Revenant or another nontoken Spirit you control dies or deals combat damage to a player, create a 1/1 white Spirit creature token with flying.

Rowdy Research

This spell costs {1} less to cast for each creature that attacked this turn.
Draw three cards.

Makindi Mesas

Makindi Mesas enters tapped.
{T}: Add {W}.

Makindi Stampede

Creatures you control get +2/+2 until end of turn.

Makindi Stampede // Makindi Mesas

Rousing of Souls

Parley — Each player reveals the top card of their library. For each nonland card revealed this way, you create a 1/1 white Spirit creature token with flying. Then each player draws a card.

Cathars' Crusade

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

Seachrome Coast

Seachrome Coast enters tapped unless you control two or fewer other lands.
{T}: Add {W} or {U}.

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.

Ghostly Pilferer

Whenever Ghostly Pilferer becomes untapped, you may pay {2}. If you do, draw a card.
Whenever an opponent casts a spell from anywhere other than their hand, draw a card.
Discard a card: Ghostly Pilferer can't be blocked this turn.

Skycloud Expanse

Deserted Beach

Deserted Beach enters tapped unless you control two or more other lands.
{T}: Add {W} or {U}.

Adarkar Wastes

{T}: Add {C}.
{T}: Add {W} or {U}. Adarkar Wastes deals 1 damage to you.

Forbidding Spirit

When Forbidding Spirit enters, until your next turn, creatures can't attack you or planeswalkers you control unless their controller pays {2} for each of those creatures.

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}

Field of Souls

Whenever a nontoken creature is put into your graveyard from the battlefield, create a 1/1 white Spirit creature token with flying.

Sol Ring

Nebelgast Herald

Flash (You may cast this spell any time you could cast an instant.)
Flying
Whenever Nebelgast Herald or another Spirit you control enters, tap target creature an opponent controls.

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.

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.

Shacklegeist

Flying
Shacklegeist can block only creatures with flying.
Tap two untapped Spirits you control: Tap target creature you don't control.