Have

Clarion Spirit

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

Getting

Sephara, Sky's Blade

You may pay {W} and tap four untapped creatures you control with flying rather than pay this spell's mana cost.
Flying, lifelink
Other creatures you control with flying have indestructible. (Damage and effects that say "destroy" don't destroy them.)

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

Bishop of Wings

Whenever an Angel you control enters, you gain 4 life.
Whenever an Angel you control dies, create a 1/1 white Spirit creature token with flying.

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.

Cavern of Souls

As Cavern of Souls enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.

Don't Have

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.")

Afterlife

Destroy target creature. It can't be regenerated. Its controller creates a 1/1 white Spirit creature token with flying.

Belfry Spirit

Flying
Haunt (When this creature dies, exile it haunting target creature.)
When Belfry Spirit enters or the creature it haunts dies, create two 1/1 black Bat creature tokens with flying.

Doomed Traveler

When Doomed Traveler dies, create a 1/1 white Spirit creature token with flying.

Baku Altar

Whenever you cast a Spirit or Arcane spell, you may put a ki counter on Baku Altar.
{2}, {T}, Remove a ki counter from Baku Altar: Create a 1/1 colorless Spirit creature token.

Benevolent Offering

Choose an opponent. You and that player each create three 1/1 white Spirit creature tokens with flying.
Choose an opponent. You gain 2 life for each creature you control and that player gains 2 life for each creature they control.

Dauntless Cathar

{1}{W}, Exile Dauntless Cathar from your graveyard: Create a 1/1 white Spirit creature token with flying. Activate only as a sorcery.

Celestial Kirin

Flying
Whenever you cast a Spirit or Arcane spell, destroy all permanents with that spell's mana value.

Spirit Bonds

Whenever a nontoken creature you control enters, you may pay {W}. If you do, create a 1/1 white Spirit creature token with flying.
{1}{W}, Sacrifice a Spirit: Target non-Spirit creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

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.

Triplicate Spirits

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.)
Create three 1/1 white Spirit creature tokens with flying.

Architect of Restoration

Vigilance
Whenever Architect of Restoration attacks or blocks, create a 1/1 colorless Spirit creature token.

The Restoration of Eiganjo

(As this Saga enters and after your draw step, add a lore counter.)
I — Search your library for a basic Plains card, reveal it, put it into your hand, then shuffle.
II — You may discard a card. When you do, return target permanent card with mana value 2 or less from your graveyard to the battlefield tapped.
III — Exile this Saga, then return it to the battlefield transformed under your control.

The Restoration of Eiganjo // Architect of Restoration

Throne of the God-Pharaoh

At the beginning of your end step, each opponent loses life equal to the number of tapped creatures you control.

Cave of the Frost Dragon

If you control two or more other lands, Cave of the Frost Dragon enters tapped.
{T}: Add {W}.
{4}{W}: Cave of the Frost Dragon becomes a 3/4 white Dragon creature with flying until end of turn. It's still a land.

Spectral Procession

Create three 1/1 white Spirit creature tokens with flying.

Court of Grace

When Court of Grace enters, you become the monarch.
At the beginning of your upkeep, create a 1/1 white Spirit creature token with flying. If you're the monarch, create a 4/4 white Angel creature token with flying instead.

Ao, the Dawn Sky

Flying, vigilance
When Ao, the Dawn Sky dies, choose one —
• Look at the top seven cards of your library. Put any number of nonland permanent cards with total mana value 4 or less from among them onto the battlefield. Put the rest on the bottom of your library in a random order.
• Put two +1/+1 counters on each permanent you control that's a creature or Vehicle.

Lantern Kami

Blessed Defiance

Target creature you control gets +2/+0 and gains lifelink until end of turn. When that creature dies this turn, create a 1/1 white Spirit creature token with flying.

Mutavault

{T}: Add {C}.
{1}: Mutavault becomes a 2/2 creature with all creature types until end of turn. It's still a land.

Kaiso, Memory of Loyalty

Flying
Remove a ki counter from Kaiso, Memory of Loyalty: Prevent all damage that would be dealt to target creature this turn.

Faithful Squire

Whenever you cast a Spirit or Arcane spell, you may put a ki counter on Faithful Squire.
At the beginning of the end step, if there are two or more ki counters on Faithful Squire, you may flip it.

Faithful Squire // Kaiso, Memory of Loyalty

Tithe Taker

During your turn, spells your opponents cast cost {1} more to cast and abilities your opponents activate cost {1} more to activate unless they're mana abilities.
Afterlife 1 (When this creature dies, create a 1/1 white and black Spirit creature token with flying.)

Selfless Spirit

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

Avacyn's Collar

Equipped creature gets +1/+0 and has vigilance.
Whenever equipped creature dies, if it was a Human, create a 1/1 white Spirit creature token with flying.
Equip {2}